BIP39 Mnemonic Generator
Generate cryptographically secure BIP39 mnemonic seed phrases (12/15/18/21/24 words) — 100% offline using the audited @scure/bip39 library
BIP39 Mnemonic Generator
Cryptographically secure HD-wallet seed phrase, generated entirely in your browser
12 words = 128 bits of entropy
Your Seed Phrase
A different passphrase derives a completely different seed — there is no way to know if the passphrase is "correct".
Validate an Existing Mnemonic
About BIP39
- •BIP39 is the standard for human-readable seed phrases used by virtually all hardware and software wallets.
- •The last word encodes a checksum, so a typo in any word usually produces an invalid phrase.
- •The seed phrase + an optional passphrase is fed through PBKDF2-HMAC-SHA512 (2048 rounds) to derive a 512-bit seed.
- •That seed is the root of an HD wallet (BIP32) — every BTC/ETH/SOL address you ever derive comes from it.
Anyone with this phrase controls all funds derived from it.
For real funds, generate seeds on a hardware wallet or a fully air-gapped machine. Never type a real seed phrase into a website you do not control. Consider this tool for learning, testnet wallets, and burner accounts only.
Generated entirely in your browser using crypto.getRandomValues() via the audited @scure/bip39 library. Nothing is sent to any server.
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