Provably fair games explained
Many crypto casino games call themselves provably fair: you can check after a round that the result was fixed before you bet and not changed. Here is how that works, and what it does not promise.

On this page
The three ingredients
- Server seedA secret random value from the site. Before the round, the site shows you only its hash, a fingerprint that cannot be reversed.
- Client seedA value from your side. You can usually change it in the game settings.
- NonceA counter that goes up by one with each bet, so every round uses a new combination.
The game combines the three to produce the result. Later the site reveals the server seed. You hash it yourself: if the hash matches the one shown before, the seed was not swapped mid-game.
How to check a round
- Note the hashed server seed before you playIt is shown in the fairness or seeds panel.
- Rotate the seed after playingThe site then reveals the old server seed.
- Run the checkUse the site's verifier, or an independent one, with the server seed, your client seed and the nonce of the bet.
- CompareThe result must match what happened in the game, and the revealed seed's hash must match the one you noted.
What provably fair does not prove
- It does not remove the house edge. A dice game with a 1% edge is fairly random and still costs you 1% of your stakes on average.
- It does not cover live dealer or most slots. Those use certified random number generators or real tables instead.
- It does not make the site pay. A fair game at a site that refuses withdrawals is still a bad deal.
- Only if you check. If nobody looks at the seeds, a dishonest site could still show fake ones. Checking a few rounds now and then keeps it honest.
Questions about provably fair
Are all crypto casino games provably fair?
No. Mostly the in-house games: dice, crash, plinko, mines. Slots from big studios and live tables use other methods.
Can a provably fair game be rigged?
Not without the check showing it, as long as you note the hash before playing and verify after.
Does provably fair mean I can win in the long run?
No. The result is fair, the payout table still keeps an edge for the house.
Where do I find the seeds?
In the game's fairness or settings panel. If a game claims to be provably fair and shows no seeds, treat the claim as marketing.