Hashed server seed
The SHA-256 digest of the casino's secret server seed, published before any bet as proof the seed is locked in.
In a provably fair setup, the hashed server seed is the commitment you get to see. The casino creates a server seed, runs it through SHA-256, and displays the resulting hash before a single bet uses that seed.
The cryptography behind it
SHA-256 only works in one direction. Nobody can recover the seed from its hash, so upcoming results remain unpredictable to you. Finding a second seed that produces the identical hash is computationally out of reach, which means the casino has no way to substitute another seed afterwards.
Keep your own copy
At the start of each session, save the hash outside the casino: a text note, a screenshot, anything the site cannot edit. Should your bet history later display a different hash, treat it as a major red flag.
Checking it after rotation
You saved the hash when the session began. Once you rotate, the casino discloses the seed. Hash that seed with our verifier or any SHA-256 utility, and compare. Every character has to be identical to what you saved. A mismatch means no result produced with that seed can be trusted.