What is Provably Fair?

Every round's outcome is fixed before you bet and can be checked by anyone afterwards — the game cannot change a result once bets are open.

1. The server picks a secret server seed and publishes only its SHA-256 hash before the round (that's the round hash under the BET button).
2. While bets are open, the client seed is gathered from the real players of this round — up to 5 of them, ordered by the committed server seed. If nobody bet, a single fixed system seed is used instead (shown honestly as a one-layer round).
3. When the round ends, the server reveals the server seed and all client seeds used.

Check the round hash

Take the revealed server seed, compute its SHA-256 yourself (the Verify button below does it in your browser with crypto.subtle), and compare it to the hash shown before the round. They must match.

Check the multiplier

The crash multiplier comes from HMAC-SHA256(key = server seed, message = client seeds joined by "-"). That HMAC decides everything: 1 round in 40 ends instantly at ×1.00, and in every other round the first 13 hex digits of the HMAC become a number h that sets the multiplier — floor((100·2^52 − h) / (2^52 − h))/100. The result is then capped at ×10,000 — the cap is applied last, on top of the fair result, and Verify applies exactly the same cap, so a capped round still matches. Verify recomputes all of this locally — no third-party site needed.

Recent rounds