Shamir Secret Sharing
Split a secret into N shares where any T reconstruct it — in your browser, nothing uploaded.
🔒 100% in your browser — nothing is uploaded
Runs entirely in your browser. Any single share (or fewer than the threshold) reveals nothing about the secret.
How it works
Split a secret (a password, seed phrase or key) into N shares such that any T of them reconstruct it, while any T−1 reveal absolutely nothing. Distribute the shares to people or places; you only need a threshold back to recover. All computation uses Shamir’s scheme over GF(256) and runs entirely in your browser — the secret and shares never leave your device.
Test with throwaway data first. For real seed phrases prefer an audited, offline implementation (e.g. SLIP-39 on a hardware wallet).
Frequently asked questions
How does it work?
Your secret becomes the constant term of a random polynomial of degree T−1; each share is a point on it. Any T points reconstruct the polynomial (and the secret) by interpolation; fewer reveal nothing.
How many shares do I need to recover?
Exactly the threshold T you chose when splitting — any T of the N shares, in any combination.
Is it safe / private?
The math is information-theoretically secure below the threshold, and everything runs locally in your browser — nothing is uploaded.