The server seed is a random value generated by the casino from which, together with your own seed, the round's result is calculated. You do not see it before the game — you see only its hash.
The timeline
1. The casino generates the seed and shows you the hash. The result is locked from that moment. 2. You play, where possible with your own client seed. 3. When you rotate the seed pair, the casino reveals the server seed in full. 4. You recompute the hash and confirm that it matches the one shown in step 1.
Why rotating matters
Until you rotate the seed pair, the server seed stays unrevealed and the check is unfinished. Practical advice: rotate the seed periodically — before a larger series, or when something feels suspicious. Every rotation closes one verifiable block.
If something is missing
If the casino does not show the hash before the game, does not allow the seed to be rotated or does not reveal it afterwards, then the provably fair badge on the page is decoration. Do the check on one round for real before you start playing with a larger amount.
The houses where the check worked in our tests are collected in the provably fair list.