js-crc

Simple CRC checksum functions for JavaScript. Supports many predefined models such as CRC-8, CRC-16, CRC-24, CRC-32, and CRC-64. It also supports custom CRC models.

Download

Core

Compress
Uncompress

Models

Compress
Uncompress

Installation

You can also install js-crc by using Bower.

bower install js-crc

For node.js, you can use this command to install:

npm install js-crc

Import

There are only 2 default models in js-crc. crc32 and crc16. More models are in js-crc/models. You can check all models in this file. The name and alias will convert to lower snake case and export. For example, CRC-64/ECMA-182 will convert to crc_64_ecma_182.

Node.js

If you use node.js, you should require the module first:

var crc32 = require('js-crc').crc32;
var crc16 = require('js-crc').crc16;
var crc_64_ecma_182 = require('js-crc/models').crc_64_ecma_182;

or

const { crc32, crc16 } = require('js-crc');
const { crc_64_ecma_182 } = require('js-crc/models');

TypeScript

If you use TypeScript, you can import like this:

import { crc32, crc16 } from 'js-crc';
import { crc_64_ecma_182 } from 'js-crc/models';

RequireJS

It supports AMD:

require(['your/path/crc.js'], function (crc) {
  var crc32 = crc.crc32;
  var crc16 = crc.crc16;
  // ...
});

Usage

Basic

You could use like this:

crc32('Message to check');
crc16('Message to check');

var crc = crc32.create();
crc.update('Message to check');
crc.hex();

var crc2 = crc32.update('Message to check');
crc2.update('Message2 to check');
crc2.array();

Custom Model

You can create custom model:

const { createModel } = require('js-crc');
var myModel = createModel({
  width: 16,
  poly: 0x8005,
  init: 0x0000,
  refin: true,
  refout: true,
  xorout: 0x0000
});
myModel('Message to check');

If width more than 32, poly, init and xorout have to split into an array of 32-bit numbers. For example

createModel({
  width: 82,
  poly: [0x0308c, 0x01110114, 0x01440411],
  init: [0, 0, 0],
  refin: true,
  refout: true,
  xorout: [0, 0, 0]
})

Example

crc32('The quick brown fox jumps over the lazy dog'); // 414fa339
crc32('The quick brown fox jumps over the lazy dog.'); // 519025e9

// It also supports byte `Array`, `Uint8Array`, `ArrayBuffer` input:
crc32([0]); // d202ef8d
crc32(new Uint8Array([0])); // d202ef8d

License

The project is released under the MIT license.

Contact

The project's website is located at https://github.com/emn178/js-crc
Author: Chen, Yi-Cyuan (emn178@gmail.com)