React Native Bip39

React Native implementation of Bitcoin BIP39. It's written in TypeScript and has direct bindings to a Bip39 C++ library. The primary function of this implementation is to provide mnemonic code for generating deterministic keys.

• 🏎️ Up to 800x faster then js solutions (mnemonicToSeed)
• ⚡️ Lightning fast implementation with pure C++ and JSI
• 📚 Standalone library
• 🧪 Tested in JS and C++ (OpenSSL)
• 💳 Made for crypto wallets

Installation

To use this library in your React Native project, run the following commands:

Start by installing Nitro Modules. You can find more information here.

bun i react-native-nitro-modules
cd ios && pod install

Now install react-native-nitro-bip39

bun install react-native-nitro-bip39

Example

import { bip39 } from "react-native-nitro-bip39";

bip39.setDefaultWordlist("english");
console.log(bip39.getDefaultWordlist());

const mnemonic = bip39.generateMnemonic(12);
console.log(mnemonic); // Outputs a 12-word mnemonic
console.log(bip39.validateMnemonic(mnemonic));
console.log(bip39.mnemonicToSeed(mnemonic));
console.log(bip39.mnemonicToSeedHex(mnemonic));
const entropy = bip39.mnemonicToEntropy(mnemonic);
console.log(entropy);
console.log(bip39.entropyToMnemonic(entropy));

Documentation

setDefaultWordlist

setDefaultWordlist(wordlist: WordLists): void

• Parameters:
  • wordlist The word list to use (e.g., 'chinese_simplified', 'english', etc.). Default is 'english'.

getDefaultWordlist

getDefaultWordlist(): WordLists

• Returns: The word list to use (e.g., 'chinese_simplified', 'english', etc.). Default is 'english'.

generateMnemonic

generateMnemonic(wordCount?: WordCount, rng?: ArrayBuffer, wordlist?: WordLists): string

• Parameters:
  • wordCount (optional): Number of words in the mnemonic (e.g., 12, 15, 18, 21, or 24). Default is 12.
  • rng (optional): A random number generator represented as a ArrayBuffer.
  • wordlist (optional): The word list to use (e.g., 'chinese_simplified', 'english', etc.). Default is 'english'.
• Returns: A string representing the generated mnemonic.

validateMnemonic

validateMnemonic(mnemonic: string, wordlist?: WordLists): boolean

• Parameters:
  • mnemonic: The mnemonic phrase to validate.
  • wordlist (optional): The word list to use (e.g., 'chinese_simplified', 'english', etc.). Default is 'english'.
• Returns: A boolean indicating whether the mnemonic is valid.

mnemonicToSeed

mnemonicToSeed(mnemonic: string, password?: string): ArrayBuffer

• Parameters:
  • mnemonic: The mnemonic phrase to convert.
  • password (optional): An optional passphrase for additional security.
• Returns: A ArrayBuffer representing the binary seed.

mnemonicToSeedHex

mnemonicToSeedHex(mnemonic: string, password?: string): string

• Parameters:
  • mnemonic: The mnemonic phrase to convert.
  • password (optional): An optional passphrase for additional security.
• Returns: A string representing the hexadecimal seed.

mnemonicToEntropy

mnemonicToEntropy(mnemonic: string, wordlist?: WordLists): string

• Parameters:
  • mnemonic: The mnemonic phrase to convert.
  • wordlist (optional): The word list to use (e.g., 'chinese_simplified', 'english', etc.). Default is 'english'.
• Returns: A string representing the binary entropy.

entropyToMnemonic

entropyToMnemonic(entropy: string | ArrayBuffer, wordlist?: WordLists): string

• Parameters:
  • entropy: The binary entropy to convert.
  • wordlist (optional): The word list to use (e.g., 'chinese_simplified', 'english', etc.). Default is 'english'.
• Returns: A string representing the mnemonic phrase.

WordLists

A type representing different word lists that can be used for generating or validating mnemonics.

type WordLists =
  | "chinese_simplified"
  | "chinese_traditional"
  | "czech"
  | "english"
  | "french"
  | "italian"
  | "japanese"
  | "korean"
  | "portuguese"
  | "spanish";

WordCount

A type representing the number of words in a mnemonic.

type WordCount = 12 | 15 | 18 | 21 | 24;

Tests

All test cases have been sourced from the Python and JavaScript implementations of BIP39. They have been subsequently adapted to be compatible with React Native.

Resources

• mrousavy/nitro Nitro Modules
• mattxlee/bip39_cpp C++ Bip39 library
• margelo/react-native-worklets-core Helpful for how JSI works
• bitcoinjs/bip39 Mostly used as bip39 reference