@larrym/lz-string

LZ-based compression algorithm for JavaScript with full ESM (ECMAScript Modules) support.

This package is a modern ESM-compatible fork of the original lz-string library by pieroxy, providing the same powerful compression capabilities with improved module support.

Features

• Full ESM (ECMAScript Modules) support
• CommonJS compatibility for legacy projects
• TypeScript type definitions included
• Zero dependencies
• Works in Node.js and browsers
• Multiple compression formats (Base64, UTF-16, URI-safe, Uint8Array)

Requirements

• Node.js >= 18.0.0

Installation

npm install @larrym/lz-string

Usage

ESM (ECMAScript Modules)

import { compress, decompress, compressToBase64, decompressFromBase64 } from '@larrym/lz-string';

// Basic compression
const compressed = compress('Hello, World!');
const decompressed = decompress(compressed);

// Base64 compression
const compressedB64 = compressToBase64('Hello, World!');
const decompressedB64 = decompressFromBase64(compressedB64);

CommonJS

const { compress, decompress } = require('@larrym/lz-string');

const compressed = compress('Hello, World!');
const decompressed = decompress(compressed);

Default Import

import LZString from '@larrym/lz-string';

const compressed = LZString.compress('Hello, World!');
const decompressed = LZString.decompress(compressed);

API

compress(input: string): string

Compresses a string and returns the compressed string.

decompress(compressed: string): string | null

Decompresses a string compressed with compress().

compressToBase64(input: string): string

Compresses a string to a Base64 encoded string.

decompressFromBase64(input: string): string | null

Decompresses a Base64 encoded string.

compressToUTF16(input: string): string

Compresses a string to UTF-16 format.

decompressFromUTF16(compressed: string): string | null

Decompresses a UTF-16 compressed string.

compressToEncodedURIComponent(input: string): string

Compresses a string to a URI-safe format.

decompressFromEncodedURIComponent(input: string): string | null

Decompresses a URI-safe compressed string.

compressToUint8Array(input: string): Uint8Array

Compresses a string to a Uint8Array.

decompressFromUint8Array(compressed: Uint8Array): string | null

Decompresses a Uint8Array.

Browser Usage

You can use this package directly in modern browsers with ESM support:

<script type="module">
  import { compress, decompress } from 'https://unpkg.com/@larrym/lz-string@1.0.0/src/lz-string.js';

  const compressed = compress('Hello, World!');
  console.log(compressed);

  const decompressed = decompress(compressed);
  console.log(decompressed);
</script>

Differences from Original lz-string

• Native ESM support with proper package.json exports
• Maintained TypeScript definitions
• Modern JavaScript syntax (const/let instead of var)
• Simplified module structure

License

MIT License - see LICENSE file for details

Original work Copyright (c) 2013 pieroxy Modified work Copyright (c) 2025 Larry Motalavigne

Credits

This package is based on the original lz-string library by pieroxy.