Interactive demo · try it yourself
The passphrase: one seed, many wallets
A passphrase — the optional "25th word" — is the most misunderstood feature in Bitcoin. This shows you exactly what it does: take one seed, add a passphrase, and you land in an entirely different wallet. Change the passphrase, change the wallet.
The seed below is randomly generated in your browser and thrown away when you leave. Never type your real seed words anywhere. There's no seed input here on purpose.
Generate a throwaway seed, then try a passphrase on it.
Runs entirely in your browser · nothing is sent, saved, or logged.
Your throwaway 12-word seed
Now add a passphrase and watch the address change:
These examples are deliberately weak — short enough to read at a glance, and exactly the kind you should not use. A real passphrase is rolled, not thought up; the passphrase rung below covers how and why.
“No passphrase” is the decoy — anyone who finds your 12 words sees only that wallet. The passphrase is what opens the hidden one, which is why it has to be backed up as carefully as the seed and stored somewhere the seed isn't. There is no reset button: forget the passphrase and that wallet is gone forever, so keeping it only in your head is the one way this setup reliably fails.
✓ Last verified: July 30, 2026