BIP39 Mnemonic Generator
Generate BIP39 mnemonic phrases for cryptocurrency wallets. Choose 12 or 24 words from the official wordlist — all client-side.
BIP39 Wordlist (first 20)
How to use BIP39 Mnemonic Generator
- Select 12 or 24 words (128 or 256 bits of entropy).
- Click Generate to create a new mnemonic.
- Copy and store the phrase securely offline.
What is BIP39 Mnemonic Generator?
BIP39 (Bitcoin Improvement Proposal 39) defines a method for generating a mnemonic sentence — a group of easy-to-remember words — that serves as a backup for cryptocurrency wallet keys. The standard uses a wordlist of 2048 words.
This tool generates cryptographically random mnemonics using the browser's Web Crypto API (crypto.getRandomValues). Nothing is stored or transmitted. Use these for testing and development — for production wallets, use a hardware wallet.
FAQ
- 12 or 24 words — which should I use?
- 12 words (128-bit entropy) is standard and widely supported. 24 words (256-bit entropy) provides higher security for large holdings.
- Is this safe for real wallets?
- This is fine for testing. For real funds, use a hardware wallet (Ledger, Trezor) to generate mnemonics in a secure environment.
- Are the words random?
- Yes. Entropy is generated using crypto.getRandomValues(), which is cryptographically secure. The checksum is computed per BIP39 spec.