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1.6.1 • Public • Published


Build Status

Read, manipulate and write spreadsheet data and styles to XLSX and JSON.

Reverse engineered from Excel spreadsheet files as a project.


npm install exceljs

New Features!


Contributions are very welcome! It helps me know what features are desired or what bugs are causing the most pain.

I have just one request; If you submit a pull request for a bugfix, please add a unit-test or integration-test (in the spec folder) that catches the problem. Even a PR that just has a failing test is fine - I can analyse what the test is doing and fix the code from that.

To be clear, all contributions added to this library will be included in the library's MIT licence.


I have to admit I'm still really snowed under at the moment and will not be able to pursue active development of exceljs in the coming months. I will however keep an eye on the pull requests and endeavour to merge and release them as they come.


  • ESLint - slowly turn on (justifyable) rules which should, I hope, help make contributions easier.
  • Conditional Formatting.
  • There are still more print-settings to add; Fixed rows/cols, etc.
  • XLSX Streaming Reader.
  • Parsing CSV with Headers



var Excel = require('exceljs');

Create a Workbook

var workbook = new Excel.Workbook();

Set Workbook Properties

workbook.creator = 'Me';
workbook.lastModifiedBy = 'Her';
workbook.created = new Date(1985, 8, 30);
workbook.modified = new Date();
workbook.lastPrinted = new Date(2016, 9, 27);
// Set workbook dates to 1904 date system
workbook.properties.date1904 = true;

Workbook Views

The Workbook views controls how many separate windows Excel will open when viewing the workbook.

workbook.views = [
    x: 0, y: 0, width: 10000, height: 20000,
    firstSheet: 0, activeTab: 1, visibility: 'visible'

Add a Worksheet

var sheet = workbook.addWorksheet('My Sheet');

Use the second parameter of the addWorksheet function to specify options for the worksheet.

For Example:

// create a sheet with red tab colour
var sheet = workbook.addWorksheet('My Sheet', {properties:{tabColor:{argb:'FFC0000'}}});
// create a sheet where the grid lines are hidden
var sheet = workbook.addWorksheet('My Sheet', {properties: {showGridLines: false}});
// create a sheet with the first row and column frozen
var sheet = workbook.addWorksheet('My Sheet', {views:[{xSplit: 1, ySplit:1}]});

Remove a Worksheet

Use the worksheet id to remove the sheet from workbook.

For Example:

// Create a worksheet
var sheet = workbook.addWorksheet('My Sheet');
// Remove the worksheet using worksheet id

Access Worksheets

// Iterate over all sheets
// Note: workbook.worksheets.forEach will still work but this is better
workbook.eachSheet(function(worksheet, sheetId) {
    // ...
// fetch sheet by name
var worksheet = workbook.getWorksheet('My Sheet');
// fetch sheet by id
var worksheet = workbook.getWorksheet(1);

Worksheet State

// make worksheet visible worksheet.state = 'show';

// make worksheet hidden worksheet.state = 'hidden';

Worksheet Properties

Worksheets support a property bucket to allow control over some features of the worksheet.

// create new sheet with properties
var worksheet = workbook.addWorksheet('sheet', {properties:{tabColor:{argb:'FF00FF00'}}});
// create a new sheet writer with properties
var worksheetWriter = workbookWriter.addSheet('sheet', {properties:{outlineLevelCol:1}});
// adjust properties afterwards (not supported by worksheet-writer)
worksheet.properties.outlineLevelCol = 2;
worksheet.properties.defaultRowHeight = 15;

Supported Properties

Name Default Description
tabColor undefined Color of the tabs
outlineLevelCol 0 The worksheet column outline level
outlineLevelRow 0 The worksheet row outline level
defaultRowHeight 15 Default row height
dyDescent 55 TBD

Worksheet Metrics

Some new metrics have been added to Worksheet...

Name Description
rowCount The total row size of the document. Equal to the row number of the last row that has values.
actualRowCount A count of the number of rows that have values. If a mid-document row is empty, it will not be included in the count.
columnCount The total column size of the document. Equal to the maximum cell count from all of the rows
actualColumnCount A count of the number of columns that have values.

Page Setup

All properties that can affect the printing of a sheet are held in a pageSetup object on the sheet.

// create new sheet with pageSetup settings for A4 - landscape
var worksheet =  workbook.addWorksheet('sheet', {
  pageSetup:{paperSize: 9, orientation:'landscape'}
// create a new sheet writer with pageSetup settings for fit-to-page
var worksheetWriter = workbookWriter.addSheet('sheet', {
  pageSetup:{fitToPage: true, fitToHeight: 5, fitToWidth: 7}
// adjust pageSetup settings afterwards
worksheet.pageSetup.margins = {
  left: 0.7, right: 0.7,
  top: 0.75, bottom: 0.75,
  header: 0.3, footer: 0.3
// Set Print Area for a sheet
worksheet.pageSetup.printArea = 'A1:G20';
// Repeat specific rows on every printed page
worksheet.pageSetup.printTitlesRow = '1:3';

Supported pageSetup settings

Name Default Description
margins Whitespace on the borders of the page. Units are inches.
orientation 'portrait' Orientation of the page - i.e. taller (portrait) or wider (landscape)
horizontalDpi 4294967295 Horizontal Dots per Inch. Default value is -1
verticalDpi 4294967295 Vertical Dots per Inch. Default value is -1
fitToPage Whether to use fitToWidth and fitToHeight or scale settings. Default is based on presence of these settings in the pageSetup object - if both are present, scale wins (i.e. default will be false)
pageOrder 'downThenOver' Which order to print the pages - one of ['downThenOver', 'overThenDown']
blackAndWhite false Print without colour
draft false Print with less quality (and ink)
cellComments 'None' Where to place comments - one of ['atEnd', 'asDisplayed', 'None']
errors 'displayed' Where to show errors - one of ['dash', 'blank', 'NA', 'displayed']
scale 100 Percentage value to increase or reduce the size of the print. Active when fitToPage is false
fitToWidth 1 How many pages wide the sheet should print on to. Active when fitToPage is true
fitToHeight 1 How many pages high the sheet should print on to. Active when fitToPage is true
paperSize What paper size to use (see below)
showRowColHeaders false Whether to show the row numbers and column letters
showGridLines false Whether to show grid lines
firstPageNumber Which number to use for the first page
horizontalCentered false Whether to center the sheet data horizontally
verticalCentered false Whether to center the sheet data vertically

Example Paper Sizes

Name Value
Letter undefined
Legal 5
Executive 7
A4 9
A5 11
B5 (JIS) 13
Envelope #10 20
Envelope DL 27
Envelope C5 28
Envelope B5 34
Envelope Monarch 37
Double Japan Postcard Rotated 82
16K 197x273 mm 119

Worksheet Views

Worksheets now support a list of views, that control how Excel presents the sheet:

  • frozen - where a number of rows and columns to the top and left are frozen in place. Only the bottom left section will scroll
  • split - where the view is split into 4 sections, each semi-independently scrollable.

Each view also supports various properties:

Name Default Description
state 'normal' Controls the view state - one of normal, frozen or split
rightToLeft false Sets the worksheet view's orientation to right-to-left
activeCell undefined The currently selected cell
showRuler true Shows or hides the ruler in Page Layout
showRowColHeaders true Shows or hides the row and column headers (e.g. A1, B1 at the top and 1,2,3 on the left
showGridLines true Shows or hides the gridlines (shown for cells where borders have not been defined)
zoomScale 100 Percentage zoom to use for the view
zoomScaleNormal 100 Normal zoom for the view
style undefined Presentation style - one of pageBreakPreview or pageLayout. Note pageLayout is not compatable with frozen views

Frozen Views

Frozen views support the following extra properties:

Name Default Description
xSplit 0 How many columns to freeze. To freeze rows only, set this to 0 or undefined
ySplit 0 How many rows to freeze. To freeze columns only, set this to 0 or undefined
topLeftCell special Which cell will be top-left in the bottom-right pane. Note: cannot be a frozen cell. Defaults to first unfrozen cell
worksheet.views = [
    {state: 'frozen', xSplit: 2, ySplit: 3, topLeftCell: 'G10', activeCell: 'A1'}

Split Views

Split views support the following extra properties:

Name Default Description
xSplit 0 How many points from the left to place the splitter. To split vertically, set this to 0 or undefined
ySplit 0 How many points from the top to place the splitter. To split horizontally, set this to 0 or undefined
topLeftCell undefined Which cell will be top-left in the bottom-right pane.
activePane undefined Which pane will be active - one of topLeft, topRight, bottomLeft and bottomRight
worksheet.views = [
    {state: 'split', xSplit: 2000, ySplit: 3000, topLeftCell: 'G10', activeCell: 'A1'}

Auto filters

It is possible to apply an auto filter to your worksheet.

worksheet.autoFilter = 'A1:C1';

While the range string is the standard form of the autoFilter, the worksheet will also support the following values:

// Set an auto filter from A1 to C1
worksheet.autoFilter = {
    from: 'A1',
    to: 'C1',
// Set an auto filter from the cell in row 3 and column 1
// to the cell in row 5 and column 12
worksheet.autoFilter = {
    from: {
        row: 3,
        column: 1
    to: {
        row: 5,
        column: 12
// Set an auto filter from D3 to the
// cell in row 7 and column 5
worksheet.autoFilter = {
    from: 'D3',
    to: {
        row: 7,
        column: 5


// Add column headers and define column keys and widths
// Note: these column structures are a workbook-building convenience only,
// apart from the column width, they will not be fully persisted.
worksheet.columns = [
    { header: 'Id', key: 'id', width: 10 },
    { header: 'Name', key: 'name', width: 32 },
    { header: 'D.O.B.', key: 'DOB', width: 10, outlineLevel: 1 }
// Access an individual columns by key, letter and 1-based column number
var idCol = worksheet.getColumn('id');
var nameCol = worksheet.getColumn('B');
var dobCol = worksheet.getColumn(3);
// set column properties
// Note: will overwrite cell value C1
dobCol.header = 'Date of Birth';
// Note: this will overwrite cell values C1:C2
dobCol.header = ['Date of Birth', 'A.K.A. D.O.B.'];
// from this point on, this column will be indexed by 'dob' and not 'DOB'
dobCol.key = 'dob';
dobCol.width = 15;
// Hide the column if you'd like
dobCol.hidden = true;
// set an outline level for columns
worksheet.getColumn(4).outlineLevel = 0;
worksheet.getColumn(5).outlineLevel = 1;
// columns support a readonly field to indicate the collapsed state based on outlineLevel
// iterate over all current cells in this column
dobCol.eachCell(function(cell, rowNumber) {
    // ...
// iterate over all current cells in this column including empty cells
dobCol.eachCell({ includeEmpty: true }, function(cell, rowNumber) {
    // ...
// add a column of new values
worksheet.getColumn(6).values = [1,2,3,4,5];
// add a sparse column of values
worksheet.getColumn(7).values = [,,2,3,,5,,7,,,,11];
// cut one or more columns (columns to the right are shifted left)
// If column properties have been definde, they will be cut or moved accordingly
// Known Issue: If a splice causes any merged cells to move, the results may be unpredictable
// remove one column and insert two more.
// Note: columns 4 and above will be shifted right by 1 column.
// Also: If the worksheet has more rows than values in the colulmn inserts,
//  the rows will still be shifted as if the values existed
var newCol3Values = [1,2,3,4,5];
var newCol4Values = ['one', 'two', 'three', 'four', 'five'];
worksheet.spliceColumns(3, 1, newCol3Values, newCol4Values);


// Add a couple of Rows by key-value, after the last current row, using the column keys
worksheet.addRow({id: 1, name: 'John Doe', dob: new Date(1970,1,1)});
worksheet.addRow({id: 2, name: 'Jane Doe', dob: new Date(1965,1,7)});
// Add a row by contiguous Array (assign to columns A, B & C)
worksheet.addRow([3, 'Sam', new Date()]);
// Add a row by sparse Array (assign to columns A, E & I)
var rowValues = [];
rowValues[1] = 4;
rowValues[5] = 'Kyle';
rowValues[9] = new Date();
// Add an array of rows
var rows = [
    [5,'Bob',new Date()], // row by array
    {id:6, name: 'Barbara', dob: new Date()}
// Get a row object. If it doesn't already exist, a new empty one will be returned
var row = worksheet.getRow(5);
// Get the last editable row in a worksheet (or undefined if there are none)
var row = worksheet.lastRow;
// Set a specific row height
row.height = 42.5;
// make row hidden
row.hidden = true;
// set an outline level for rows
worksheet.getRow(4).outlineLevel = 0;
worksheet.getRow(5).outlineLevel = 1;
// rows support a readonly field to indicate the collapsed state based on outlineLevel
row.getCell(1).value = 5; // A5's value set to 5
row.getCell('name').value = 'Zeb'; // B5's value set to 'Zeb' - assuming column 2 is still keyed by name
row.getCell('C').value = new Date(); // C5's value set to now
// Get a row as a sparse array
// Note: interface change: worksheet.getRow(4) ==> worksheet.getRow(4).values
row = worksheet.getRow(4).values;
// assign row values by contiguous array (where array element 0 has a value)
row.values = [1,2,3];
// assign row values by sparse array  (where array element 0 is undefined)
var values = []
values[5] = 7;
values[10] = 'Hello, World!';
row.values = values;
expect(row.getCell(10).value).toEqual('Hello, World!');
// assign row values by object, using column keys
row.values = {
    id: 13,
    name: 'Thing 1',
    dob: new Date()
// Insert a page break below the row
// Iterate over all rows that have values in a worksheet
worksheet.eachRow(function(row, rowNumber) {
    console.log('Row ' + rowNumber + ' = ' + JSON.stringify(row.values));
// Iterate over all rows (including empty rows) in a worksheet
worksheet.eachRow({ includeEmpty: true }, function(row, rowNumber) {
    console.log('Row ' + rowNumber + ' = ' + JSON.stringify(row.values));
// Iterate over all non-null cells in a row
row.eachCell(function(cell, colNumber) {
    console.log('Cell ' + colNumber + ' = ' + cell.value);
// Iterate over all cells in a row (including empty cells)
row.eachCell({ includeEmpty: true }, function(cell, colNumber) {
    console.log('Cell ' + colNumber + ' = ' + cell.value);
// Cut one or more rows (rows below are shifted up)
// Known Issue: If a splice causes any merged cells to move, the results may be unpredictable
// remove one row and insert two more.
// Note: rows 4 and below will be shifted down by 1 row.
var newRow3Values = [1,2,3,4,5];
var newRow4Values = ['one', 'two', 'three', 'four', 'five'];
worksheet.spliceRows(3, 1, newRow3Values, newRow4Values);
// Cut one or more cells (cells to the right are shifted left)
// Note: this operation will not affect other rows
// remove one cell and insert two more (cells to the right of the cut cell will be shifted right)
row.splice(4,1,'new value 1', 'new value 2');
// Commit a completed row to stream
// row metrics
var rowSize = row.cellCount;
var numValues = row.actualCellCount;

Handling Individual Cells

var cell = worksheet.getCell('C3');
// Modify/Add individual cell
cell.value = new Date(1968, 5, 1);
// query a cell's type
// use string value of cell
myInput.value = cell.text;
// use html-safe string for rendering...
var html = '<div>' + cell.html + '</div>';

Merged Cells

// merge a range of cells
// ... merged cells are linked
worksheet.getCell('B5').value = 'Hello, World!';
// ... merged cells share the same style object
worksheet.getCell('B5').style.font = myFonts.arial;
// unmerging the cells breaks the style links
// merge by top-left, bottom-right
worksheet.mergeCells('G10', 'H11');
worksheet.mergeCells(10,11,12,13); // top,left,bottom,right

Defined Names

Individual cells (or multiple groups of cells) can have names assigned to them. The names can be used in formulas and data validation (and probably more).

// assign (or get) a name for a cell (will overwrite any other names that cell had)
worksheet.getCell('A1').name = 'PI';
// assign (or get) an array of names for a cell (cells can have more than one name)
worksheet.getCell('A1').names = ['thing1', 'thing2'];
expect(worksheet.getCell('A1').names).to.have.members(['thing1', 'thing2']);
// remove a name from a cell

Data Validations

Cells can define what values are valid or not and provide prompting to the user to help guide them.

Validation types can be one of the following:

Type Description
list Define a discrete set of valid values. Excel will offer these in a dropdown for easy entry
whole The value must be a whole number
decimal The value must be a decimal number
textLength The value may be text but the length is controlled
custom A custom formula controls the valid values

For types other than list or custom, the following operators affect the validation:

Operator Description
between Values must lie between formula results
notBetween Values must not lie between formula results
equal Value must equal formula result
notEqual Value must not equal formula result
greaterThan Value must be greater than formula result
lessThan Value must be less than formula result
greaterThanOrEqual Value must be greater than or equal to formula result
lessThanOrEqual Value must be less than or equal to formula result
// Specify list of valid values (One, Two, Three, Four).
// Excel will provide a dropdown with these values.
worksheet.getCell('A1').dataValidation = {
    type: 'list',
    allowBlank: true,
    formulae: ['"One,Two,Three,Four"']
// Specify list of valid values from a range.
// Excel will provide a dropdown with these values.
    worksheet.getCell('A1').dataValidation = {
        type: 'list',
        allowBlank: true,
        formulae: ['$D$5:$F$5']
// Specify Cell must be a whole number that is not 5.
// Show the user an appropriate error message if they get it wrong
worksheet.getCell('A1').dataValidation = {
    type: 'whole',
    operator: 'notEqual',
    showErrorMessage: true,
    formulae: [5],
    errorStyle: 'error',
    errorTitle: 'Five',
    error: 'The value must not be Five'
// Specify Cell must be a decomal number between 1.5 and 7.
// Add 'tooltip' to help guid the user
worksheet.getCell('A1').dataValidation = {
    type: 'decimal',
    operator: 'between',
    allowBlank: true,
    showInputMessage: true,
    formulae: [1.5, 7],
    promptTitle: 'Decimal',
    prompt: 'The value must between 1.5 and 7'
// Specify Cell must be have a text length less than 15
worksheet.getCell('A1').dataValidation = {
    type: 'textLength',
    operator: 'lessThan',
    showErrorMessage: true,
    allowBlank: true,
    formulae: [15]
// Specify Cell must be have be a date before 1st Jan 2016
worksheet.getCell('A1').dataValidation = {
    type: 'date',
    operator: 'lessThan',
    showErrorMessage: true,
    allowBlank: true,
    formulae: [new Date(2016,0,1)]


Cells, Rows and Columns each support a rich set of styles and formats that affect how the cells are displayed.

Styles are set by assigning the following properties:

// assign a style to a cell
ws.getCell('A1').numFmt = '0.00%';
// Apply styles to worksheet columns
ws.columns = [
    { header: 'Id', key: 'id', width: 10 },
    { header: 'Name', key: 'name', width: 32, style: { font: { name: 'Arial Black' } } },
    { header: 'D.O.B.', key: 'DOB', width: 10, style: { numFmt: 'dd/mm/yyyy' } }
// Set Column 3 to Currency Format
ws.getColumn(3).numFmt = '"£"#,##0.00;[Red]\-"£"#,##0.00';
// Set Row 2 to Comic Sans.
ws.getRow(2).font = { name: 'Comic Sans MS', family: 4, size: 16, underline: 'double', bold: true };

When a style is applied to a row or column, it will be applied to all currently existing cells in that row or column. Also, any new cell that is created will inherit its initial styles from the row and column it belongs to.

If a cell's row and column both define a specific style (e.g. font), the cell will use the row style over the column style. However if the row and column define different styles (e.g. column.numFmt and row.font), the cell will inherit the font from the row and the numFmt from the column.

Caveat: All the above properties (with the exception of numFmt, which is a string), are JS object structures. If the same style object is assigned to more than one spreadsheet entity, then each entity will share the same style object. If the style object is later modified before the spreadsheet is serialized, then all entities referencing that style object will be modified too. This behaviour is intended to prioritize performance by reducing the number of JS objects created. If you want the style objects to be independent, you will need to clone them before assigning them. Also, by default, when a document is read from file (or stream) if spreadsheet entities share similar styles, then they will reference the same style object too.

Number Formats

// display value as '1 3/5'
ws.getCell('A1').value = 1.6;
ws.getCell('A1').numFmt = '# ?/?';
// display value as '1.60%'
ws.getCell('B1').value = 0.016;
ws.getCell('B1').numFmt = '0.00%';


// for the wannabe graphic designers out there
ws.getCell('A1').font = {
    name: 'Comic Sans MS',
    family: 4,
    size: 16,
    underline: true,
    bold: true
// for the graduate graphic designers...
ws.getCell('A2').font = {
    name: 'Arial Black',
    color: { argb: 'FF00FF00' },
    family: 2,
    size: 14,
    italic: true
// note: the cell will store a reference to the font object assigned.
// If the font object is changed afterwards, the cell font will change also...
var font = { name: 'Arial', size: 12 };
ws.getCell('A3').font = font;
font.size = 20; // Cell A3 now has font size 20!
// Cells that share similar fonts may reference the same font object after
// the workbook is read from file or stream
Font Property Description Example Value(s)
name Font name. 'Arial', 'Calibri', etc.
family Font family for fallback. An integer value. 1 - Serif, 2 - Sans Serif, 3 - Mono, Others - unknown
scheme Font scheme. 'minor', 'major', 'none'
charset Font charset. An integer value. 1, 2, etc.
color Colour description, an object containing an ARGB value. { argb: 'FFFF0000'}
bold Font weight true, false
italic Font slope true, false
underline Font underline style true, false, 'none', 'single', 'double', 'singleAccounting', 'doubleAccounting'
strike Font strikethrough true, false
outline Font outline true, false


// set cell alignment to top-left, middle-center, bottom-right
ws.getCell('A1').alignment = { vertical: 'top', horizontal: 'left' };
ws.getCell('B1').alignment = { vertical: 'middle', horizontal: 'center' };
ws.getCell('C1').alignment = { vertical: 'bottom', horizontal: 'right' };
// set cell to wrap-text
ws.getCell('D1').alignment = { wrapText: true };
// set cell indent to 1
ws.getCell('E1').alignment = { indent: 1 };
// set cell text rotation to 30deg upwards, 45deg downwards and vertical text
ws.getCell('F1').alignment = { textRotation: 30 };
ws.getCell('G1').alignment = { textRotation: -45 };
ws.getCell('H1').alignment = { textRotation: 'vertical' };

Valid Alignment Property Values

horizontal vertical wrapText indent readingOrder textRotation
left top true integer rtl 0 to 90
center middle false ltr -1 to -90
right bottom vertical
fill distributed
justify justify


// set single thin border around A1
ws.getCell('A1').border = {
    top: {style:'thin'},
    left: {style:'thin'},
    bottom: {style:'thin'},
    right: {style:'thin'}
// set double thin green border around A3
ws.getCell('A3').border = {
    top: {style:'double', color: {argb:'FF00FF00'}},
    left: {style:'double', color: {argb:'FF00FF00'}},
    bottom: {style:'double', color: {argb:'FF00FF00'}},
    right: {style:'double', color: {argb:'FF00FF00'}}
// set thick red cross in A5
ws.getCell('A5').border = {
    diagonal: {up: true, down: true, style:'thick', color: {argb:'FFFF0000'}}

Valid Border Styles

  • thin
  • dotted
  • dashDot
  • hair
  • dashDotDot
  • slantDashDot
  • mediumDashed
  • mediumDashDotDot
  • mediumDashDot
  • medium
  • double
  • thick


// fill A1 with red darkVertical stripes
ws.getCell('A1').fill = {
    type: 'pattern',
// fill A2 with yellow dark trellis and blue behind
ws.getCell('A2').fill = {
    type: 'pattern',
// fill A3 with blue-white-blue gradient from left to right
ws.getCell('A3').fill = {
    type: 'gradient',
    gradient: 'angle',
    degree: 0,
    stops: [
        {position:0, color:{argb:'FF0000FF'}},
        {position:0.5, color:{argb:'FFFFFFFF'}},
        {position:1, color:{argb:'FF0000FF'}}
// fill A4 with red-green gradient from center
ws.getCell('A2').fill = {
    type: 'gradient',
    gradient: 'path',
    stops: [
        {position:0, color:{argb:'FFFF0000'}},
        {position:1, color:{argb:'FF00FF00'}}

Pattern Fills

Property Required Description
type Y Value: 'pattern'
Specifies this fill uses patterns
pattern Y Specifies type of pattern (see Valid Pattern Types below)
fgColor N Specifies the pattern foreground color. Default is black.
bgColor N Specifies the pattern background color. Default is white.

Valid Pattern Types

  • none
  • solid
  • darkVertical
  • darkGray
  • mediumGray
  • lightGray
  • gray125
  • gray0625
  • darkHorizontal
  • darkVertical
  • darkDown
  • darkUp
  • darkGrid
  • darkTrellis
  • lightHorizontal
  • lightVertical
  • lightDown
  • lightUp
  • lightGrid
  • lightTrellis
  • lightGrid

Gradient Fills

Property Required Description
type Y Value: 'gradient'
Specifies this fill uses gradients
gradient Y Specifies gradient type. One of ['angle', 'path']
degree angle For 'angle' gradient, specifies the direction of the gradient. 0 is from the left to the right. Values from 1 - 359 rotates the direction clockwise
center path For 'path' gradient. Specifies the relative coordinates for the start of the path. 'left' and 'top' values range from 0 to 1
stops Y Specifies the gradient colour sequence. Is an array of objects containing position and color starting with position 0 and ending with position 1. Intermediary positions may be used to specify other colours on the path.


Using the interface above it may be possible to create gradient fill effects not possible using the XLSX editor program. For example, Excel only supports angle gradients of 0, 45, 90 and 135. Similarly the sequence of stops may also be limited by the UI with positions [0,1] or [0,0.5,1] as the only options. Take care with this fill to be sure it is supported by the target XLSX viewers.

Rich Text

Individual cells now support rich text or in-cell formatting. Rich text values can control the font properties of any number of sub-strings within the text value. See Fonts for a complete list of details on what font properties are supported.

ws.getCell('A1').value = {
  'richText': [
     {'font': {'size': 12,'color': {'theme': 0},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': 'This is '},
     {'font': {'italic': true,'size': 12,'color': {'theme': 0},'name': 'Calibri','scheme': 'minor'},'text': 'a'},
     {'font': {'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': ' '},
     {'font': {'size': 12,'color': {'argb': 'FFFF6600'},'name': 'Calibri','scheme': 'minor'},'text': 'colorful'},
     {'font': {'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': ' text '},
     {'font': {'size': 12,'color': {'argb': 'FFCCFFCC'},'name': 'Calibri','scheme': 'minor'},'text': 'with'},
     {'font': {'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': ' in-cell '},
     {'font': {'bold': true,'size': 12,'color': {'theme': 1},'name': 'Calibri','family': 2,'scheme': 'minor'},'text': 'format'}
expect(ws.getCell('A1').text).to.equal('This is a colorful text with in-cell format');

Outline Levels

Excel supports outlining; where rows or columns can be expanded or collapsed depending on what level of detail the user wishes to view.

Outline levels can be defined in column setup:

worksheet.columns = [
    { header: 'Id', key: 'id', width: 10 },
    { header: 'Name', key: 'name', width: 32 },
    { header: 'D.O.B.', key: 'DOB', width: 10, outlineLevel: 1 }

Or directly on the row or column

worksheet.getColumn(3).outlineLevel = 1;
worksheet.getRow(3).outlineLevel = 1;

The sheet outline levels can be set on the worksheet

// set column outline level
worksheet.properties.outlineLevelCol = 1;
// set row outline level
worksheet.properties.outlineLevelRow = 1;

Note: adjusting outline levels on rows or columns or the outline levels on the worksheet will incur a side effect of also modifying the collapsed property of all rows or columns affected by the property change. E.g.:

worksheet.properties.outlineLevelCol = 1;
worksheet.getColumn(3).outlineLevel = 1;
worksheet.properties.outlineLevelCol = 2;

The outline properties can be set on the worksheet

worksheet.properties.outlineProperties = {
  summaryBelow: false,
  summaryRight: false,


Adding images to a worksheet is a two-step process. First, the image is added to the workbook via the addImage() function which will also return an imageId value. Then, using the imageId, the image can be added to the worksheet either as a tiled background or covering a cell range.

Note: As of this version, adjusting or transforming the image is not supported.

Add Image to Workbook

The Workbook.addImage function supports adding images by filename or by Buffer. Note that in both cases, the extension must be specified. Valid extension values include 'jpeg', 'png', 'gif'.

// add image to workbook by filename
var imageId1 = workbook.addImage({
  filename: 'path/to/image.jpg',
  extension: 'jpeg',
// add image to workbook by buffer
var imageId2 = workbook.addImage({
  buffer: fs.readFileSync('path/to.image.png'),
  extension: 'png',
// add image to workbook by base64
var myBase64Image = "data:image/png;base64,iVBORw0KG...";
var imageId2 = workbook.addImage({
  base64: myBase64Image,
  extension: 'png',

Add image background to worksheet

Using the image id from Workbook.addImage, the background to a worksheet can be set using the addBackgroundImage function

// set background

Add image over a range

Using the image id from Workbook.addImage, an image can be embedded within the worksheet to cover a range. The coordinates calculated from the range will cover from the top-left of the first cell to the bottom right of the second.

// insert an image over B2:D6
worksheet.addImage(imageId2, 'B2:D6');

Using a structure instead of a range string, it is possible to partially cover cells.

Note that the coordinate system used for this is zero based, so the top-left of A1 will be { col: 0, row: 0 }. Fractions of cells can be specified by using floating point numbers, e.g. the midpoint of A1 is { col: 0.5, row: 0.5 }.

// insert an image over part of B2:D6
worksheet.addImage(imageId2, {
  tl: { col: 1.5, row: 1.5 },
  br: { col: 3.5, row: 5.5 }

The cell range can also have the eproperty 'editAs' which will control how the image is anchored to the cell(s) It can have one of the following values:

Value Description
undefined This is the default. It specifies the image will be moved and sized with cells
oneCell Image will be moved with cells but not sized
absolute Image will not be moved or sized with cells
ws.addImage(imageId, {
  tl: { col: 0.1125, row: 0.4 },
  br: { col: 2.101046875, row: 3.4 },
  editAs: 'oneCell'

File I/O


Reading XLSX

// read from a file
var workbook = new Excel.Workbook();
    .then(function() {
        // use workbook
// pipe from stream
var workbook = new Excel.Workbook();

Writing XLSX

// write to a file
var workbook = createAndFillWorkbook();
    .then(function() {
        // done
// write to a stream
    .then(function() {
        // done


Reading CSV

// read from a file
var workbook = new Excel.Workbook();
    .then(function(worksheet) {
        // use workbook or worksheet
// read from a stream
var workbook = new Excel.Workbook();
    .then(function(worksheet) {
        // use workbook or worksheet
// pipe from stream
var workbook = new Excel.Workbook();
// read from a file with European Dates
var workbook = new Excel.Workbook();
var options = {
    dateFormats: ['DD/MM/YYYY']
workbook.csv.readFile(filename, options)
    .then(function(worksheet) {
        // use workbook or worksheet
// read from a file with custom value parsing
var workbook = new Excel.Workbook();
var options = {
    map: function(value, index) {
        switch(index) {
            case 0:
                // column 1 is string
                return value;
            case 1:
                // column 2 is a date
                return new Date(value);
            case 2:
                // column 3 is JSON of a formula value
                return JSON.parse(value);
                // the rest are numbers
                return parseFloat(value);
workbook.csv.readFile(filename, options)
    .then(function(worksheet) {
        // use workbook or worksheet

The CSV parser uses fast-csv to read the CSV file. The options passed into the read functions above is also passed to fast-csv for parsing of the csv data. Please refer to the fast-csv README.md for details.

Dates are parsed using the npm module moment. If no dateFormats are supplied, the following are used:

  • moment.ISO_8601
  • 'MM-DD-YYYY'
  • 'YYYY-MM-DD'

Writing CSV

// write to a file
var workbook = createAndFillWorkbook();
    .then(function() {
        // done
// write to a stream
// Be careful that you need to provide sheetName or
// sheetId for correct import to csv.
workbook.csv.write(stream, { sheetName: 'Page name' })
    .then(function() {
        // done
// read from a file with European Date-Times
var workbook = new Excel.Workbook();
var options = {
    dateFormat: 'DD/MM/YYYY HH:mm:ss',
    dateUTC: true, // use utc when rendering dates
workbook.csv.readFile(filename, options)
    .then(function(worksheet) {
        // use workbook or worksheet
// read from a file with custom value formatting
var workbook = new Excel.Workbook();
var options = {
    map: function(value, index) {
        switch(index) {
            case 0:
                // column 1 is string
                return value;
            case 1:
                // column 2 is a date
                return moment(value).format('YYYY-MM-DD');
            case 2:
                // column 3 is a formula, write just the result
                return value.result;
                // the rest are numbers
                return value;
workbook.csv.readFile(filename, options)
    .then(function(worksheet) {
        // use workbook or worksheet

The CSV parser uses fast-csv to write the CSV file. The options passed into the write functions above is also passed to fast-csv for writing the csv data. Please refer to the fast-csv README.md for details.

Dates are formatted using the npm module moment. If no dateFormat is supplied, moment.ISO_8601 is used. When writing a CSV you can supply the boolean dateUTC as true to have ExcelJS parse the date without automatically converting the timezone using moment.utc().

Streaming I/O

The File I/O documented above requires that an entire workbook is built up in memory before the file can be written. While convenient, it can limit the size of the document due to the amount of memory required.

A streaming writer (or reader) processes the workbook or worksheet data as it is generated, converting it into file form as it goes. Typically this is much more efficient on memory as the final memory footprint and even intermediate memory footprints are much more compact than with the document version, especially when you consider that the row and cell objects are disposed once they are committed.

The interface to the streaming workbook and worksheet is almost the same as the document versions with a few minor practical differences:

  • Once a worksheet is added to a workbook, it cannot be removed.
  • Once a row is committed, it is no longer accessible since it will have been dropped from the worksheet.
  • unMergeCells() is not supported.

Note that it is possible to build the entire workbook without committing any rows. When the workbook is committed, all added worksheets (including all uncommitted rows) will be automatically committed. However in this case, little will have been gained over the Document version.

Streaming XLSX

Streaming XLSX Writer

The streaming XLSX writer is available in the ExcelJS.stream.xlsx namespace.

The constructor takes an optional options object with the following fields:

Field Description
stream Specifies a writable stream to write the XLSX workbook to.
filename If stream not specified, this field specifies the path to a file to write the XLSX workbook to.
useSharedStrings Specifies whether to use shared strings in the workbook. Default is false
useStyles Specifies whether to add style information to the workbook. Styles can add some performance overhead. Default is false

If neither stream nor filename is specified in the options, the workbook writer will create a StreamBuf object that will store the contents of the XLSX workbook in memory. This StreamBuf object, which can be accessed via the property workbook.stream, can be used to either access the bytes directly by stream.read() or to pipe the contents to another stream.

// construct a streaming XLSX workbook writer with styles and shared strings
var options = {
    filename: './streamed-workbook.xlsx',
    useStyles: true,
    useSharedStrings: true
var workbook = new Excel.stream.xlsx.WorkbookWriter(options);

In general, the interface to the streaming XLSX writer is the same as the Document workbook (and worksheets) described above, in fact the row, cell and style objects are the same.

However there are some differences...


As seen above, the WorkbookWriter will typically require the output stream or file to be specified in the constructor.

Committing Data

When a worksheet row is ready, it should be committed so that the row object and contents can be freed. Typically this would be done as each row is added...

   id: i,
   name: theName,
   etc: someOtherDetail

The reason the WorksheetWriter does not commit rows as they are added is to allow cells to be merged across rows:

worksheet.getCell('A1').value = 'I am merged';
worksheet.getCell('C1').value = 'I am not';
worksheet.getCell('C2').value = 'Neither am I';
worksheet.getRow(2).commit(); // now rows 1 and two are committed.

As each worksheet is completed, it must also be committed:

// Finished adding data. Commit the worksheet

To complete the XLSX document, the workbook must be committed. If any worksheet in a workbook are uncommitted, they will be committed automatically as part of the workbook commit.

// Finished the workbook.
  .then(function() {
    // the stream has been written


A portion of this library has been isolated and tested for use within a browser environment.

Due to the streaming nature of the workbook reader and workbook writer, these have not been included. Only the document based workbook may be used (see Create a Worbook for details).

For example code using ExcelJS in the browser take a look at the spec/browser folder in the github repo.


The following files are pre-bundled and included inside the dist folder.

  • exceljs.js
  • exceljs.min.js

Value Types

The following value types are supported.

Null Value

Enum: Excel.ValueType.Null

A null value indicates an absence of value and will typically not be stored when written to file (except for merged cells). It can be used to remove the value from a cell.


worksheet.getCell('A1').value = null;

Merge Cell

Enum: Excel.ValueType.Merge

A merge cell is one that has its value bound to another 'master' cell. Assigning to a merge cell will cause the master's cell to be modified.

Number Value

Enum: Excel.ValueType.Number

A numeric value.


worksheet.getCell('A1').value = 5;
worksheet.getCell('A2').value = 3.14159;

String Value

Enum: Excel.ValueType.String

A simple text string.


worksheet.getCell('A1').value = 'Hello, World!';

Date Value

Enum: Excel.ValueType.Date

A date value, represented by the JavaScript Date type.


worksheet.getCell('A1').value = new Date(2017, 2, 15);

Hyperlink Value

Enum: Excel.ValueType.Hyperlink

A URL with both text and link value.


// link to web
worksheet.getCell('A1').value = { text: 'www.mylink.com', hyperlink: 'http://www.mylink.com' };
// internal link
worksheet.getCell('A1').value = { text: 'Sheet2', hyperlink: '#\\"Sheet2\\"!A1' };

Formula Value

Enum: Excel.ValueType.Formula

An Excel formula for calculating values on the fly. Note that while the cell type will be Formula, the cell may have an effectiveType value that will be derived from the result value.

Note that ExcelJS cannot process the formula to generate a result, it must be supplied.


worksheet.getCell('A3').value = { formula: 'A1+A2', result: 7 };

Cells also support convenience getters to access the formula and result:

worksheet.getCell('A3').formula === 'A1+A2';
worksheet.getCell('A3').result === 7;

Shared Formula

Shared formulae enhance the compression of the xlsx document by increasing the repetition of text within the worksheet xml.

A shared formula can be assigned to a cell using a new value form:

worksheet.getCell('B3').value = { sharedFormula: 'A3', result: 10 };

This specifies that the cell B3 is a formula that will be derived from the formula in A3 and its result is 10.

The formula convenience getter will translate the formula in A3 to what it should be in B3:

worksheet.getCell('B3').formula === 'B1+B2';

Formula Type

To distinguish between real and translated formula cells, use the formulaType getter:

worksheet.getCell('A3').formulaType === Enums.FormulaType.Master;
worksheet.getCell('B3').formulaType === Enums.FormulaType.Shared;

Formula type has the following values:

Name Value
Enums.FormulaType.None 0
Enums.FormulaType.Master 1
Enums.FormulaType.Shared 2

Rich Text Value

Enum: Excel.ValueType.RichText

Rich, styled text.


worksheet.getCell('A1').value = {
  richText: [
    { text: 'This is '},
    {font: {italic: true}, text: 'italic'},

Boolean Value

Enum: Excel.ValueType.Boolean


worksheet.getCell('A1').value = true;
worksheet.getCell('A2').value = false;

Error Value

Enum: Excel.ValueType.Error


worksheet.getCell('A1').value = { error: '#N/A' };
worksheet.getCell('A2').value = { error: '#VALUE!' };

The current valid Error text values are:

Name Value
Excel.ErrorValue.NotApplicable #N/A
Excel.ErrorValue.Ref #REF!
Excel.ErrorValue.Name #NAME?
Excel.ErrorValue.DivZero #DIV/0!
Excel.ErrorValue.Null #NULL!
Excel.ErrorValue.Value #VALUE!
Excel.ErrorValue.Num #NUM!

Interface Changes

Every effort is made to make a good consistent interface that doesn't break through the versions but regrettably, now and then some things have to change for the greater good.



The arguments in the callback function to Worksheet.eachRow have been swapped and changed; it was function(rowNumber,rowValues), now it is function(row, rowNumber) which gives it a look and feel more like the underscore (_.each) function and prioritises the row object over the row number.


This function has changed from returning a sparse array of cell values to returning a Row object. This enables accessing row properties and will facilitate managing row styles and so on.

The sparse array of cell values is still available via Worksheet.getRow(rowNumber).values;



cell.styles renamed to cell.style


Promises returned from functions switched from Bluebird to native node Promise which can break calling code if they rely on Bluebird's extra features.

To mitigate this the following two changes were added to 0.3.0:

  • A more fully featured and still browser compatable promise lib is used by default. This lib supports many of the features of Bluebird but with a much lower footprint.
  • An option to inject a different Promise implementation. See Config section for more details.


ExcelJS now supports dependency injection for the promise library. You can restore Bluebird promises by including the following code in your module...

ExcelJS.config.setValue('promise', require('bluebird'));

Please note: I have tested ExcelJS with bluebird specifically (since up until recently this was the library it used). From the tests I have done it will not work with Q.

Known Issues

Testing with PhantomJS

You may need to install phantomjs globally before running the browser-test script.

It's also possible that phantomjs will not run (or can't be found). If this happens, try the following:

sudo apt-get install libfontconfig

Splice vs Merge

If any splice operation affects a merged cell, the merge group will not be moved correctly

Release History

Version Changes
  • Bug Fixes
    • More textual data written properly to xml (including text, hyperlinks, formula results and format codes)
    • Better date format code recognition
  • Cell Font Style
  • Fixed potential race condition on zip write
  • Bug Fixes
    • Now handles 10 or more worksheets in one workbook
    • theme1.xml file properly added and referenced
  • Cell Borders
  • Bug Fixes
    • More compatable theme1.xml included in XLSX file
  • Cell Fills
  • Bug Fixes
    • More compatable theme1.xml included in XLSX file
    • Fixed filename case issue
  • Cell Fills
  • Bug Fixes
    • Added docProps files to satisfy Mac Excel users
    • Fixed filename case issue
    • Fixed worksheet id issue
  • Core Workbook Properties
  • Bug Fixes
    • Handles File Not Found error
  • CSV Files
  • Streaming XLSX Writer
    • At long last ExcelJS can support writing massive XLSX files in a scalable memory efficient manner. Performance has been optimised and even smaller spreadsheets can be faster to write than the document writer. Options have been added to control the use of shared strings and styles as these can both have a considerable effect on performance
  • Worksheet.lastRow
    • Access the last editable row in a worksheet.
  • Row.commit()
    • For streaming writers, this method commits the row (and any previous rows) to the stream. Committed rows will no longer be editable (and are typically deleted from the worksheet object). For Document type workbooks, this method has no effect.
  • One Billion Cells
    • Achievement Unlocked: A simple test using ExcelJS has created a spreadsheet with 1,000,000,000 cells. Made using random data with 100,000,000 rows of 10 cells per row. I cannot validate the file yet as Excel will not open it and I have yet to implement the streaming reader but I have every confidence that it is good since 1,000,000 rows loads ok.
  • Bug Fixes
  • Streaming XLSX Writer
    • At long last ExcelJS can support writing massive XLSX files in a scalable memory efficient manner. Performance has been optimised and even smaller spreadsheets can be faster to write than the document writer. Options have been added to control the use of shared strings and styles as these can both have a considerable effect on performance
  • Worksheet.lastRow
    • Access the last editable row in a worksheet.
  • Row.commit()
    • For streaming writers, this method commits the row (and any previous rows) to the stream. Committed rows will no longer be editable (and are typically deleted from the worksheet object). For Document type workbooks, this method has no effect.
  • Data Validations
    • Cells can now define validations that controls the valid values the cell can have
  • Fixed "read property 'richText' of undefined error. Thanks to james075
  • Refactoring Complete. All unit and integration tests pass.
  • Merged Fall back to JSON.stringify() if unknown Cell.Type #137 with some modification. If a cell value is assigned to an unrecognisable javascript object, the stored value in xlsx and csv files will be JSON stringified. Note that if the file is read again, no attempt will be made to parse the stringified JSON text. Thanks to wulfsolter for the contribution.
  • Merged Protect cell fix #166. This does not mean full support for protected cells merely that the parser is not confused by the extra xml. Thanks to jayflo for the contribution.
  • Added functions to delete cells, rows and columns from a worksheet. Modelled after the Array splice method, the functions allow cells, rows and columns to be deleted (and optionally inserted). See Columns and Rows for details.
    Note: Not compatable with cell merges
  • Merged Fix issue #178 #201. Adds the following properties to workbook:
    • title
    • subject
    • keywords
    • category
    • description
    • company
    • manager
    Thanks to stavenko for the contribution.
  • Browser Compatable!
    • Well mostly. I have added a browser sub-folder that contains a browserified bundle and an index.js that can be used to generate another. See Browser section for details.
  • Fixed corrupted theme.xml. Apologies for letting that through.
  • Merged [BUGFIX] data validation formulae undefined #253. Thanks to jayflo for the contribution.
  • Reduced Dependencies.
    • Goodbye lodash, goodbye bluebird. Minified bundle is now just over half what it was in the first version.
  • Addressed the following issues:

    These issues are potentially caused by a bug that caused colours with zero themes, tints or indexes to be rendered and parsed incorrectly.

    Regarding themes: the theme files stored inside the xlsx container hold important information regarding colours, styles etc and if the theme information from a loaded xlsx file is lost, the results can be unpredictable and undesirable. To address this, when an ExcelJS Workbook parses an XLSX file, it will preserve any theme files it finds and include them when writing to a new XLSX. If this behaviour is not desired, the Workbook class exposes a clearThemes() function which will drop the theme content. Note that this behaviour is only implemented in the document based Workbook class, not the streamed Reader and Writer.

  • Switching to transpiled code for distribution. This will ensure compatability with 4.0.0 and above from here on. And it will also allow use of much more expressive JS code in the lib folder!
  • Basic Image Support!Images can now be added to worksheets either as a tiled background or stretched over a range. Note: other features like rotation, etc. are not supported yet and will reqeuire further work.


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