Generate cryptographically secure BIP39 mnemonic recovery phrases for any cryptocurrency wallet. 12 to 24 words, multiple languages, instant entropy visualisation.
Follows the official BIP39 standard used by Ledger, Trezor, MetaMask, and virtually all modern crypto wallets.
All generation happens in your browser using the Web Crypto API. Nothing is sent to any server, ever.
Real-time entropy meter shows the strength of your phrase in bits, helping you choose the right word count.
Generate phrases in English, Spanish, French, Italian, and Japanese (romaji) to suit your preference.
Paste an existing mnemonic to check its validity, word count, and BIP39 compliance instantly.
Add an optional BIP39 passphrase (sometimes called the 25th word) for an extra layer of security.
Cryptographically random bits are generated using the Web Crypto API (CSPRNG).
A checksum is appended by hashing the entropy, ensuring phrase validity and error detection.
Bits are split into 11-bit groups, each mapped to one of 2048 BIP39 words.
The result is your mnemonic phrase – a human-readable representation of your wallet seed.
Combined with an optional passphrase, a 512-bit seed is derived via PBKDF2 (2048 iterations).
A mnemonic phrase generator creates the cryptographic foundation for your cryptocurrency wallet — a carefully ordered sequence of words that encodes your master private key. Standardised under BIP39 (Bitcoin Improvement Proposal 39), these phrases typically contain 12 or 24 words drawn from a fixed list of 2,048 English terms.
Also called a seed phrase, recovery phrase, or backup phrase, this word sequence allows you to restore full access to your wallet on any compatible software or hardware, even if your device is lost or destroyed. For example, phrases like abandon ability able about above absent follow specific linguistic rules to minimise transcription errors.
The security of a mnemonic phrase comes from its entropy — the number of random bits it encodes. A 12-word phrase carries 128 bits of entropy (roughly 2¹²⁸ possible combinations), while a 24-word phrase uses 256 bits, making it computationally impossible to guess. You can optionally add a custom passphrase (the so-called "25th word") for an additional security layer, creating a completely different wallet from the same word sequence. Always write your phrase on paper, store it offline, and never enter it into any website you did not generate it on.
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