Lean QR is a lightweight yet fully-featured library for generating QR Codes. It
runs in Node.js and all recent browsers, and includes wrapper components for
React, Preact,
Vue, and
native Web Components. Under 4kB
compressed.

Features

- ISO 18004 compliant;
- Lightweight (less than 4kB compressed, ~7kB uncompressed, no dependencies);
- still too big? There's also an
even smaller "nano" export
which has reduced features to fit into ~2kB compressed, ~4kB uncompressed!
- Simple yet flexible API, with sensible defaults for all configuration;
- Supports all standard encodings
out-of-the box:
- including Unicode 😎;
- and Shift-JIS 漢字;
- and supports custom modes for
special requirements;
- Automatic encoding to minimise output size;
- Fast enough for lag-free live editing;
- Comprehensive automated testing;
- Multiple output formats
(canvas /
PNG /
SVG /
text).

You can see it in action online, or try it from the
terminal:

``shell
npx lean-qr 'MY MESSAGE HERE'
`

Basic Usage

See the Quickstart documentation
for Node.js / Browser / React / Preact / Vue / Web Components / CLI usage.

`shell
npm install --save lean-qr
`

`html



`

`javascript
import { generate } from 'lean-qr';

const qrCode = generate('LEAN-QR LIBRARY');
qrCode.toCanvas(document.getElementById('my-qr-code'));
`

Troubleshooting

$3

There is a bug in JSDOM which
prevents this class being available in tests. This issue only affects JSDOM, and
can be fixed with:

`js
import { TextEncoder, TextDecoder } from 'node:util';
global.TextEncoder = TextEncoder;
global.TextDecoder = TextDecoder;
`

You can put this in the test file or in Jest's setupFilesAfterEnv` config. You
should _not_ put this in your application code.

Full Documentation

- Quickstart
- API Reference
- Source Code
- Comparison With Other Libraries