Nachos Pillage Milwaukee

    TypeScript icon, indicating that this package has built-in type declarations

    3.0.2 • Public • Published

    QuickChart for Javascript

    npm npm Build Status

    This is a Javascript client for, a web service for generating static charts. View the main QuickChart repository here.


    If you are using npm:

    npm install quickchart-js


    This library provides a QuickChart object. Import it, instantiate it, and set your Chart.js config:

    const QuickChart = require('quickchart-js');
    const myChart = new QuickChart();
      type: 'bar',
      data: { labels: ['Hello world', 'Foo bar'], datasets: [{ label: 'Foo', data: [1, 2] }] },

    Use getUrl() on your quickchart object to get the encoded URL that renders your chart:

    // Prints:

    If you have a large or complicated chart, use getShortUrl() on your quickchart object to get a fixed-length URL using the web service:

    const url = await myChart.getShortUrl();
    // Prints:

    Or write it to disk:


    The URLs produce this chart image:

    Creating a QuickChart object

    If you have an account ID and API key, authenticate using the QuickChart constructor:

    const qc = new QuickChart(apiKey, accountId);

    To use the free (community) version, leave it blank:

    const qc = new QuickChart();

    Customizing your chart

    setConfig(chart: Object | string)

    Use this config to customize the Chart.js config object that defines your chart. You must set this before generating a URL!

    setWidth(width: int)

    Sets the width of the chart in pixels. Defaults to 500.

    setHeight(height: int)

    Sets the height of the chart in pixels. Defaults to 300.

    setFormat(format: string)

    Sets the format of the chart. Defaults to png. svg is also valid.

    setBackgroundColor(color: string)

    Sets the background color of the chart. Any valid HTML color works. Defaults to #ffffff (white). Also takes rgb, rgba, and hsl values.

    setDevicePixelRatio(ratio: float)

    Sets the device pixel ratio of the chart. This will multiply the number of pixels by the value. This is usually used for retina displays. Defaults to 1.0.

    setVersion(version: string)

    Sets the Chart.js version to use (e.g. 2.9.4 or 3.4.0). Valid options are shown in the documentation.

    Getting outputs

    There are two ways to get a URL for your chart object.

    getUrl(): string

    Returns a URL that will display the chart image when loaded.

    getShortUrl(): Promise

    Uses the web service to create a fixed-length chart URL that displays the chart image. The Promise resolves with a URL such as

    Note that short URLs expire after a few days for users of the free service. You can subscribe to keep them around longer.

    getSignedUrl(): string

    Returns a URL that displays the chart image. It is signed with your user account to bypass rate limitations.

    toBinary(): Promise

    Creates a binary buffer that contains your chart image.

    toDataUrl(): Promise

    Returns a base 64 data URL beginning with data:image/png;base64.

    toFile(pathOrDescriptor: PathLike | FileHandle): Promise

    Given a filepath string or a writable file handle, creates a file containing your chart image.

    More examples

    Check out the examples/ directory to see other usage. Here's a simple test that uses some of the custom parameters:

    const qc = new QuickChart();
      type: 'bar',
      data: { labels: ['Hello world', 'Foo bar'], datasets: [{ label: 'Foo', data: [1, 2] }] },

    Here's a more complicated chart that includes some Javascript:

      type: 'bar',
      data: {
        labels: ['January', 'February', 'March', 'April', 'May'],
        datasets: [
            label: 'Dogs',
            data: [50, 60, 70, 180, 190],
      options: {
        scales: {
          yAxes: [
              ticks: {
                callback: function (value) {
                  return '$' + value;

    As we customize these charts, the URLs are getting a little long for my liking. There's a getShortUrl function that uses the web service to generate a short(er), fixed-length URL:

    // Fill the chart with data from 0 to 100
    const data = [...Array(100).keys()];
      type: 'bar',
      data: { labels: ['Hello world', 'Foo bar'], datasets: [{ label: 'Foo', data }] },
    async function printShortUrl() {
      const url = await qc.getShortUrl();

    Using built-in QuickChart functions

    QuickChart has builtin functions: getImageFill, getGradientFill, getGradientFillHelper, and pattern.draw. These functions can be accessed via the QuickChart class. For example:

    const qc = new QuickChart();
      type: 'bar',
      data: {
        labels: ['Hello world', 'Foo bar'],
        datasets: [
            label: 'Foo',
            data: [1, 2],
            backgroundColor: QuickChart.getGradientFillHelper('horizontal', ['red', 'green']),

    Building the library

    To build this library locally, run:

    yarn build

    To run tests:

    yarn test

    If you're editing the library and running examples, you may want to continuously build the library in the background:

    yarn build:watch
    # ...
    node examples/simple_example.js




    npm i quickchart-js

    DownloadsWeekly Downloads






    Unpacked Size

    209 kB

    Total Files


    Last publish


    • ianw