Provably fair
Provably fair is a cryptographic scheme that lets a player independently verify that a game result was fixed before their bet and was not altered afterwards.
Before a round the server generates a secret seed and publishes its hash — a commitment it cannot change later. The player contributes a client seed, and the outcome is derived from both together with a nonce. After the round the server reveals the original seed so anyone can re-hash it, confirm it matches the published commitment, and recompute the result.
It proves the specific round was not tampered with. It does not change the house edge, and it is used mainly in crypto-native crash, dice and mines titles rather than in certified RNG slots, which rely on laboratory testing instead.
- Server seed hash published before the bet
- Client seed supplied by the player
- Server seed revealed after the round for verification
- Proves integrity of a round, not a better return
Frequently asked questions
Does provably fair mean better odds?
No. The house edge is unchanged; the scheme only proves the published result was determined honestly.
Is it a replacement for RNG certification?
No. Regulated markets still require independent laboratory testing of the generator and paytable.