Secret Split
Break a secret into n shares so that any k bring it back and anything less reveals nothing. For seed phrases, master passwords and recovery keys that must not live in one place — or with one person.
0 / 1024 bytes — a seed phrase, a master password, a recovery key.
3 of 5
Enter a secret and press Split secret.
Split in your browser with crypto.getRandomValues; nothing is sent anywhere. The weak point is afterwards — “Copy all” and the .txt put every share in one place, so hand them out and delete the copy.
Where it fits
A 2-of-3 backup of a wallet seed across home, a safe and a relative. A 3-of-5 root credential held by a team, so no single admin can use it and no single departure can lose it.
Nothing, not “less”
Unlike cutting a password in half, a share is not a piece of the secret. Two shares of a 3-of-n split are consistent with every possible secret equally — that is information-theoretic, not a matter of computing power.
What it does not do
It does not stop k holders from colluding, and it does not detect a share that was deliberately forged — the checksum only catches typos. The page makes no network requests; for a real seed, load it once and go offline.