Provably fair in a crypto casino: how it really works
Provably fair means you can check afterwards that a round was drawn from numbers fixed before you placed the bet. At BAKS.BET the server derives every outcome from HMAC-SHA256 of a secret server seed, your client seed and a bet counter called the nonce. The SHA-256 hash of the server seed is shown before you play. When you rotate your seeds, the old server seed is revealed, so you can recompute past rounds and compare the hash. This proves a round was not altered after your bet. It does not prove the RTP and it does not help you win.
Key facts
- Algorithm
- HMAC-SHA256
- Committed before play
- SHA-256 hash of the server seed
- You control
- client seed (can be changed)
- Counter
- nonce, grows with every bet
- Where you can verify
- instant games (Fair panel)
- Slots
- player check page currently off
The three ingredients: server seed, client seed, nonce
The server seed is a long random secret generated on our side. You never see it while it is in use, but you do see its SHA-256 hash. A hash works like a sealed envelope: it is practically impossible to find a different seed that gives the same hash, so showing the hash up front commits the server to one seed.
The client seed is your contribution. It has a default value and you can set your own text. Because the server cannot know it in advance if you change it, the server cannot tune the seed to your input.
The nonce is a counter of your bets under the current seed pair: 0, 1, 2 and so on. It makes every round different even though both seeds stay the same.
How a result is produced
For each round the server computes HMAC-SHA256 with the server seed as the key and the string clientSeed:nonce:cursor as the message. The cursor counts how many random numbers the round needs. A card draw or a bomb layout may need several, so the cursor steps forward and the output bytes are turned into numbers.
That number then becomes the outcome by a fixed rule of the game: a crash point, a Dice roll, the position of mines, a card. The win and the RNG are computed only on the server. Your browser draws the picture and cannot influence the result.
How to verify a round
In the instant games there is a Fair panel. It shows the current hash of the server seed, your client seed and the nonce, and lets you rotate the seeds. Rotation closes the current pair: the old server seed is revealed and a new one is committed with a new hash.
After rotation, take the revealed server seed and check two things. First, that its SHA-256 equals the hash you saw before you played. Second, that recomputing your rounds from the seed, your client seed and each nonce gives exactly the results you got. The panel can verify rounds for you, and Crash also has a separate verify page at /instant/crash/verify. If you prefer not to trust our page, any HMAC-SHA256 tool gives the same outputs.
Slots: what is and is not available
Slots use the same commit and reveal scheme on the server, and the data for each round is recorded. However, the player-facing check page for slots is currently switched off. We say it openly: today you can verify instant games yourself, but for slots there is no public checking screen.
So for slots the guarantee rests on our records and on the rule that the result is computed only on the server, not on something you can recompute in the browser. If this matters to you, play instant games such as Dice or Mines, where the whole check is available.
What provably fair does not prove
It proves one narrow thing: that the outcome was fixed by the committed seeds and was not changed after you bet. It does not prove that the game's RTP is what is declared. That comes from the game math and the figure in the info panel, and only a very large number of rounds shows it in practice. See what RTP means.
It also does not make results more favourable, does not reveal future rounds, and does not remove the house edge. Instant games return 92% on average (Dice 97%), which means the casino keeps the rest in the long run, however fair each single round is.
- A verified round only means the draw matched the seeds.
- A losing streak is not evidence of cheating, and a winning one is not evidence of honesty.
- Seeds do not let you predict the next result.
Practical tips
Set your own client seed before you start if you want to, and rotate seeds from time to time, so the older rounds can be checked. Save the hash shown before you play, because the comparison is meaningless without it.
Remember that fairness is not the same as safety for your budget. Play for entertainment only, set a limit in advance and read responsible gambling. The rules of each game are on the rules page. You must be 18+.
Frequently asked questions
Does provably fair mean I will win more often?
No. It only lets you check that a round was drawn from seeds fixed before the bet. The house edge stays the same: instant games return 92% on average, Dice 97%, and no seed setting changes your odds.
What is a nonce?
A counter of your bets under the current seed pair. It starts at 0 and grows by one with every bet. Together with the server seed and your client seed it makes each round's random numbers different.
Why is the server seed hidden at first?
If it were visible while in use, you could predict the next results. So only its SHA-256 hash is shown. After you rotate seeds, the old server seed is revealed and you can confirm it matches the earlier hash.
Can I verify slot spins?
Not on a public page: the player-facing check for slots is currently switched off. Commit and reveal data are still recorded per round on the server. Instant games do have the Fair panel and verification.
Does this prove the RTP is correct?
No. A verified round shows only that the result was not changed after your bet. RTP is a statistical property of the game math visible only over very many rounds. The declared figure is in the game's info panel.
Can I change my client seed?
Yes. You can set your own client seed, and the nonce counts your bets with it. Changing it is optional, but it is a good habit before a session if you want your own input in every draw.
Read next
Updated: 2026-11-04. 18+. Gambling can be addictive: stake only what you can afford to lose.