Audited & minimal implementation of BIP32 hierarchical deterministic (HD) wallets over secp256k1.

• 🔒 Audited by an independent security firm
• 🔻 Tree-shaking-friendly: use only what's necessary, other code won't be included
• 📦 ESM and common.js
• ➰ Only 3 audited dependencies by the same author: noble-curves, noble-hashes, and scure-base
• 🪶 Only 418KB all-bundled: much smaller than similar libraries

Check out scure-bip39 if you need mnemonic phrases. See ed25519-keygen if you need SLIP-0010/BIP32 ed25519 hdkey implementation.

scure — secure, independently audited packages for every use case.

• Zero or minimal dependencies
• Highly readable TypeScript / JS code
• PGP-signed releases and transparent NPM builds with provenance
• Check out homepage & all libraries: base, bip32, bip39, btc-signer, starknet

npm install @scure/bip32

This module exports a single class HDKey, which should be used like this:

const { HDKey } = require("@scure/bip32");
const hdkey1 = HDKey.fromMasterSeed(seed);
const hdkey2 = HDKey.fromExtendedKey(base58key);
const hdkey3 = HDKey.fromJSON({ xpriv: string });

// props
[hdkey1.depth, hdkey1.index, hdkey1.chainCode];
console.log(hdkey2.privateKey, hdkey2.publicKey);
console.log(hdkey3.derive("m/0/2147483647'/1"));
const sig = hdkey3.sign(hash);
hdkey3.verify(hash, sig);

Note: chainCode property is essentially a private part of a secret "master" key, it should be guarded from unauthorized access.

The full API is:

class HDKey {
  public static HARDENED_OFFSET: number;
  public static fromMasterSeed(seed: Uint8Array, versions: Versions): HDKey;
  public static fromExtendedKey(base58key: string, versions: Versions): HDKey;
  public static fromJSON(json: { xpriv: string }): HDKey;

  readonly versions: Versions;
  readonly depth: number = 0;
  readonly index: number = 0;
  readonly chainCode: Uint8Array | null = null;
  readonly parentFingerprint: number = 0;

  get fingerprint(): number;
  get identifier(): Uint8Array | undefined;
  get pubKeyHash(): Uint8Array | undefined;
  get privateKey(): Uint8Array | null;
  get publicKey(): Uint8Array | null;
  get privateExtendedKey(): string;
  get publicExtendedKey(): string;

  derive(path: string): HDKey;
  deriveChild(index: number): HDKey;
  sign(hash: Uint8Array): Uint8Array;
  verify(hash: Uint8Array, signature: Uint8Array): boolean;
  wipePrivateData(): this;
}

interface Versions {
  private: number;
  public: number;
}

The hdkey submodule provides a library for keys derivation according to BIP32.

It has almost the exact same API than the version 1.x of hdkey from cryptocoinjs, but it's backed by this package's primitives, and has built-in TypeScript types. Its only difference is that it has to be be used with a named import. The implementation is loosely based on hdkey, which has MIT License.

The library has been independently audited:

• at version 1.0.1, in Jan 2022, by cure53
  • PDFs: online, offline
  • Changes since audit.
  • The audit has been funded by Ethereum Foundation with help of Nomic Labs

The library was initially developed for js-ethereum-cryptography. At commit ae00e6d7, it was extracted to a separate package called micro-bip32. After the audit we've decided to use @scure NPM namespace for security.

MIT License

Copyright (c) 2022 Patricio Palladino, Paul Miller (paulmillr.com)