Zero-knowledge secret splitter
Split an API key, password, or any short secret into shares using Shamir's Secret Sharing. Any k of your chosen n shares rebuild it — no single share, and no server, ever holds the whole thing.
Best for short secrets (keys, passwords) — not whole documents.
Split into 3 shares.
Need any 2 of them to rebuild it.
How this actually works
The math
Your secret's bytes become points on a random polynomial over a finite field (GF(256)). Each share is one point. With fewer than k points, the original polynomial — and your secret — is mathematically undetermined, not just "hard to guess".
The randomness
Polynomial coefficients come from crypto.getRandomValues(), the same cryptographically secure source browsers use for encryption keys — not Math.random().
No database
There's nothing to breach. Shares only exist in the browser tab that generated them, and wherever you choose to send them.