Provably fair Crash verifier

Recompute any Crash round from the revealed server seed, your client seed and the nonce. House edge: ~3% (incl. instant bust).

Crash takes the first 52 bits of the round hash. If that number divides by 33, the round busts instantly at 1.00x — that is the house edge made visible. Otherwise the crash point is computed as (100·2^52 − h) / (2^52 − h) / 100.

Every player in the same round shares the same crash point — one verification covers the whole round.

Odds and payouts

Roughly 1-in-33 rounds bust instantly. Survival past a multiplier m is ≈ 0.97 / m.

How to verify a crash round yourself

  1. Rotate or end the seed pair in your account so the casino reveals the server seed it committed to. Until that happens the hash is a promise, not a proof.
  2. Copy the revealed server seed, your client seed and the nonce of the round you want to check — the nonce is the round counter, not a timestamp.
  3. Paste all three into the verifier above. It recomputes the HMAC chain and derives the crash outcome the same way the operator's server did.
  4. Compare the result with what your bet history shows. A mismatch on any single round is the only evidence of tampering that actually means something.
  5. Check the committed hash too: hash the revealed server seed and confirm it equals the hash the casino published before you played.

Verification proves the result was not changed after you bet. It does not make crash profitable — the ~3% (incl. instant bust) house edge is applied openly, in the payout table, and it is unaffected by any of this.

Frequently asked

The casino crashed at 1.00x — was I cheated?

Instant busts are part of the published construction (~3% of rounds). Verify the hash: if h mod 33 = 0, the 1.00x result was determined before the round started.

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