Provably Fair Verifier
Verify any casino roll for fairness.
Provably fair is a cryptographic system that lets players verify that each roll, spin, or hand was fair — not manipulated by the casino. Used by crypto casinos and some modern RNG-based operators. This verifier takes the server seed, client seed, and nonce from any provably fair game and confirms the outcome matches what the casino displayed.
Enter the server seed, client seed, and nonce from the casino's "verify" page. The calculator computes the expected hash and compares it to the outcome shown. If they match, the roll was provably fair. If they don't, the casino is manipulating outcomes and you should withdraw any funds immediately and report to the casino's licensing authority.
For UKGC-regulated casinos: provably fair verification isn't needed because the casino is independently audited by GLI or BMM, and their games use certified RNGs. For offshore crypto casinos (Curacao, Anjouan): provably fair is the only player-side check available. We maintain a list of reputable offshore casinos at /crypto-casinos — only those with provably fair games are listed.
Provably Fair Verifier
Enter server and client seeds to independently verify game outcomes from provably fair crypto casinos.
What Is Provably Fair?
Provably fair is a cryptographic system used by crypto casinos to prove that game outcomes weren't manipulated. The casino provides a server seed hash before the game, you provide a client seed, and after the game the full server seed is revealed — letting you independently verify the result.