Generate 1D and 2D barcodes

barcode generator

Generate 1D and 2D barcodes

npm install barcode

Set it up and specify your type and options. The following 3 are the only required ones.

var barcode = require('barcode');
var code39 = barcode('code39', {
    data: "it works",
    width: 400,
    height: 100,

Next choose from the three methods below how you want to output your barcode.


Get a stream of the final image data. you can collect this and save out a new PNG (default type), pipe it elsewhere, or save it to a CDN.

code39.getStream(function (errreadStream) {
    if (err) throw err;
    // 'readStream' is an instance of ReadableStream 

File to disk

Save an image out to the file system, pretty simple. Just be sure to specify your outfile.

var outfile = path.join(__dirname, 'imgs', 'mycode.png')
code39.saveImage(outfile, function (err) {
    if (err) throw err;
    console.log('File has been written!');

Base64 encoded img src

Often times, barcodes are single use for a single print or whatever. With this method, we can create one on the fly and just send the base64 encoded image to the browser through the HTML.

code39.getBase64(function (errimgsrc) {
    if (err) throw err;
    // if we're using HTTP or another framework 
    res.end('<img src="' + imgsrc + '">');

Much of this will be due for a rewrite in the near future. 2.0 might make some API changes, but I will keep it as close to the original as possible.

Some goals for the rewrite:

  • Externalize as much as possible
    • checksum calculations
    • error correcting calculations
  • Abstract the drawing part
    • Allow for the 3 ways to accept the data currently implemented
    • Be able to print numbers below barcodes
  • Break the process up into more defined and testable steps
    • Check for issues with settings
    • Calculate checksums (if applicable)
    • Create pattern in a data structure
    • Send the pattern to the drawer

I hope to eventually make it more maintainable this way instead of the endless amounts of spaghetti code.

The MIT License (MIT)