Check the casino's maths yourself
Every original game on Stake, Shuffle and BC.Game commits to a result before you bet. Paste the seeds from your bet history and this page recomputes the outcome from scratch — the same HMAC, the same extraction, the same arithmetic. If the numbers match, the bet was settled exactly as promised.
Three inputs, one deterministic answer
1 · The casino commits first
Before you bet, the casino generates a secret server seed and shows you only its SHA-256 hash. It cannot change the seed afterwards without breaking that hash, so the outcome is locked in before you play.
2 · You add entropy
Your client seed is yours to set, and the nonce counts up with every bet. Because you control part of the input, the casino cannot pick a server seed that engineers a particular result against you.
3 · The outcome is derived
The three values are signed with HMAC and the digest is turned into numbers by a published rule — floor(float × 10000) / 100 for a dice roll, a Fisher–Yates shuffle for a mine layout. Same inputs, same output, every time.
4 · You rotate and check
Rotating your seed pair reveals the old server seed. Hash it yourself to confirm it matches the commitment you were shown, then replay your bets here. Only bets placed before the rotation can be verified.
Does any of my data leave this page?
No. The seeds you type stay in the browser tab. After the page loads, the hashing runs through the browser's built-in Web Crypto API and makes no network requests. You can confirm this by opening DevTools and watching the Network panel while you verify a bet.
My result doesn't match the casino. What went wrong?
Nearly always one of three things. You may be using the hashed server seed instead of the revealed one; the nonce may belong to a different bet; or the seed pair may not be the one that was active when the bet was placed. Check all three before concluding anything is wrong — and note that a genuine mismatch is worth reporting to the casino.
Why do Crash and Slide ask for different inputs?
Stake settles Crash and Slide from a pre-committed hash chain shared by every player in the round, not from your personal seed pair. Those two tools therefore take the round's game hash and the public chain seed instead of a client seed and nonce. Shuffle and BC.Game settle Crash per bet, so their versions use the usual three inputs.
What are the pattern and target finders for?
They replay a range of nonces against a seed pair you already hold and report which ones would have produced a given outcome. That is an auditing aid for seeds you have finished with — it cannot predict future results, because the next server seed is still secret. Anyone selling "prediction" software built on this idea is selling you nothing.
Is a provably fair game the same as a fair bet?
No, and the distinction matters. Provable fairness means the casino did not tamper with the outcome after the fact. It says nothing about the house edge, which is built into the payout table and is working against you on every single bet no matter how honest the draw was.