@vandeurenglenn/base-x

Fast, optimized, and compatible base-x encoding/decoding library.

This library is a high-performance drop-in replacement for the standard base-x library. It includes transparent optimizations for power-of-2 bases (Base16, Base32, Base64), achieving 5x-7x faster performance while maintaining full backward compatibility.

It also introduces optional RFC 4648 compliance for standard Hex, Base32, and Base64 implementations.

Install

npm i -S @vandeurenglenn/base-x

Features

• High Performance: Automatically switches to a customized bitwise algorithm for bases that are powers of 2 (16, 32, 64), offering significant speedups over generic integer arithmetic.
• Backwards Compatible: By default, it mimics the behavior of the original base-x library (integer-based encoding, preserving leading zero characters), making it safe for use in cryptocurrency applications (e.g., Bitcoin Base58).
• RFC 4648 Support: Optional mode to strictly follow RFC standards (padding, 8-bit block alignment) for standard web/network use cases.
• TypeScript: First-class TypeScript support with included type definitions.

Usage

Standard Mode (Drop-in Replacement)

Behaves exactly like base-x. Note: This mode follows the "Bitcoin-style" integer encoding (leading zero preservation, no padding).

import base from '@vandeurenglenn/base-x'

const BASE58 = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
const bs58 = base(BASE58)

const data = new Uint8Array([0, 255])
const encoded = bs58.encode(data)
console.log(encoded) // "1LU" (1 preserves the leading zero byte)

const decoded = bs58.decode(encoded)
console.log(decoded) // Uint8Array [0, 255]

RFC 4648 Mode (Standard Base64/Hex/Base32)

Enable this mode if you need standard padding (=) and strict behavior matching built-in browser/Node.js methods.

import base from '@vandeurenglenn/base-x'

const BASE64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
// Enable RFC 4648 compliance
const b64 = base(BASE64, { rfc4648: true })

const data = new TextEncoder().encode('Hello World')

// Encodes with padding
const encoded = b64.encode(data)
console.log(encoded) // "SGVsbG8gV29ybGQ="

// Decodes standard Base64 string
const decoded = b64.decode(encoded)
console.log(new TextDecoder().decode(decoded)) // "Hello World"

Performance

Benchmarks run on Node.js v25:

| Algorithm | @vandeurenglenn/base-x | standard base-x | Speedup | |-----------|------------------------|-----------------|---------| | Base16| ~3,400,000 ops/sec | ~516,000 ops/sec| ~6.5x| | Base32| ~4,100,000 ops/sec | ~680,000 ops/sec| ~6.0x| | Base64| ~4,900,000 ops/sec | ~878,000 ops/sec| ~5.5x| | Base58| ~600,000 ops/sec | ~594,000 ops/sec| ~1.0x |

License

MIT © base-x contributors & Vandeuren Glenn