Reconstruct a Secret
Paste your Shamir shares below to recover the original secret. You need at least T shares (the threshold).
Paste shares and click Reconstruct to recover the secret
All splitting and reconstruction happens in your browser using GF(256) finite field arithmetic. Your secret and its shares are never stored or sent to a server.
Shamir Secret Sharing FAQ
How do I combine shares back into the secret?
Paste at least Threshold many shares, each exactly as it was handed to you: the index, a hyphen, then the hex. The index before the hyphen is the coordinate that share was evaluated at, so it has to travel with the hex. A bare hex string with the index stripped off is unusable.
What if I have fewer shares than the threshold?
It refuses, and tells you how many it needs against how many it got. This is not a limit to work around: below the threshold the shares carry no information about the contents of the secret, so there is nothing left to recover from them, by this tool or any other.
Does the order I paste the shares in matter?
No. Each share carries its own index, so the tool identifies them whatever order they arrive in, and any Threshold many of them work equally well. There is no privileged first share and no need to remember which custodian held which one.
What if a share is corrupted or belongs to a different secret?
Two cases are caught: a share whose length does not match the others is rejected as inconsistent, and a share missing its index is rejected as malformed. A share that is corrupted but still the right length is NOT caught, because a share carries no checksum — the tool will combine it and hand back a wrong secret rather than an error. Check that the reconstructed value looks like what you expected before relying on it.
Need to share secrets securely?
Use CredenShare to deliver sensitive data with end-to-end encryption, expiration controls, and full audit logging.