Verify your casino result.
Prove it was fair.
Paste your server seed, client seed and nonce. Faircheck recomputes the exact outcome with the same HMAC-SHA256 math the casino used — so you can check Dice, Limbo, Mines, Plinko, Roulette, Keno, Wheel and Hi-Lo yourself. Nothing leaves your browser.
Three inputs, one provable outcome
Before the bet, the casino shows the SHA-256 hash of a secret server seed. It is now locked in — it cannot change.
Your result is HMAC-SHA256(server seed, `client seed:nonce:round`), turned into a float, then mapped to the game. You control the client seed.
Rotate your seeds to reveal the server seed. Faircheck hashes it to match the commitment and recomputes every roll.
Pick a game to verify
The 0.00–100.00 roll, recomputed from your seeds.
The crash-style target multiplier, with the house edge exposed.
The single-zero European pocket, 0–36.
The ball’s left/right path and final bin.
Which of the 25 tiles were mines.
The 10 numbers drawn from 40.
The winning segment of the wheel.
The drawn card from a 52-card deck.
The round’s crash multiplier, from the game hash.
32 casinos, one algorithm
Questions
What is a provably-fair verifier?
A tool that recomputes a casino game result from its public inputs — the server seed, your client seed and the nonce — so you can confirm the outcome was determined before the bet and never altered. Faircheck does this entirely in your browser.
Do I have to trust Faircheck?
No. The verification is pure math (HMAC-SHA256) running locally on your device. Your seeds are never sent anywhere. You can read the open algorithm and even run the same computation yourself.
Which casinos does it cover?
Every casino on the “Stake method” — the HMAC-SHA256 seed/nonce scheme used by 32+ crypto casinos including Stake, BC.Game, Roobet, Shuffle and Rollbit. The math is identical; only seed-rotation menus differ.
My result does not match — is the casino cheating?
Usually it is a seed or nonce mismatch: make sure you rotated your seed pair so the server seed is revealed (unhashed), and that the nonce is the exact bet number. For Limbo/Wheel, the operator’s house edge or segment count must match too. A genuine mismatch on correct inputs is the red flag worth screenshotting.