BIP39 passphrase
Generate a BIP39 mnemonic and its entropy, or convert an existing mnemonic back.
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About the bip39 passphrase
Produces a BIP39 mnemonic from fresh entropy, or takes a phrase you already have and shows the entropy behind it. The checksum is validated against the standard English wordlist, so a mistyped or misremembered word is caught immediately.
Frequently asked questions
Is it safe to generate a wallet seed in a browser?
Treat anything generated in a browser tab as practice material. For a wallet holding real value, use a hardware device that generates the seed on-chip and never exposes it to a general-purpose computer.
Why 12 or 24 words?
Word count follows entropy: 128 bits gives 12 words, 256 bits gives 24. Twelve words is already far beyond brute-force reach; 24 is chosen for margin rather than present-day necessity.