QR Code Encoder

A lightweight library generating stylish QR codes that also support gradient fills and rounded corners in only 12.2kB minified (4.75kB gzipped). Try out the demo!

Origin

This library is a trimmed down version of Lars Jung's jQuery.qrcode library. Our library is however not based on jQuery anymore and doesnt make use of it. Lars Jung's library itself is based on this QR code Generator.

All parts are licensed under the MIT License.

Installation

To install via npm:

npm install --save qr-creator

To install via yarn:

yarn add qr-creator

Or use a cdn like jsdelivr or unpkg (see usage).

Usage

The library is available as a module and non-module version. To import it as a module:

  // from installed package for bundling with a module bundler like webpack:
  import QrCreator from 'qr-creator';
  // from cdn:
  import QrCreator from 'https://cdn.jsdelivr.net/npm/qr-creator/dist/qr-creator.es6.min.js';

To use the non-module version:

  <!-- from your project's code base -->
  <script src="path/to/qr-creator.min.js"></script>
  <!-- from cdn -->
  <script src="https://cdn.jsdelivr.net/npm/qr-creator/dist/qr-creator.min.js"></script>

Call the QrCreator API with a configuration object and a DOM element or canvas to render the QR code into:

  QrCreator.render({
    text: 'some text',
    radius: 0.5, // 0.0 to 0.5
    ecLevel: 'H', // L, M, Q, H
    fill: '#536DFE', // foreground color
    background: null, // color or null for transparent
    size: 128 // in pixels
  }, document.querySelector('#qr-code'));

If you want to fill the QR code with a gradient, use the following format:

{
    type: 'radial-gradient', // or 'linear-gradient'
    position: [ ... ],
    colorStops: [
        [ offset0, color0 ],
        [ offset1, color1 ],
        ...
    ]
}

Where the position is specified as in createLinearGradient / createRadialGradient. However, each value is relative to the QR code size, i.e. will be multiplied by that size to yield the absolute position.

Trimmed down to be low weight

The goal of the library is to generate QR codes only. For that reason we have removed all additional code such as GIF image generation, background image support, rendering a label on top, removed some dead code, and freed it from depending on jQuery. Also, the resulting library does not use any global variables, is all strict mode, and relies on modern browser standards instead.

Building

To install the dependencies run:

npm install

and then to build the project:

npm run build