sha256 --verify fairness
Verify the game instead of trusting the casino
Provably fair games commit to their outcomes cryptographically before you bet. We explain the hashing, the seeds and the probability behind crash, dice, plinko and mines — and show you how to recompute any result yourself.
Verify a result yourself
Paste a revealed server seed, your client seed and a nonce into our in-browser verifier. It checks the SHA-256 commitment and recomputes the roll with HMAC-SHA512 — every intermediate value shown, nothing leaves your browser.
How it works in 60 seconds
the full explanation →- 01 / commit
commit
The casino generates a secret server seed and publishes its SHA-256 hash. The hash locks the seed in place: any later change would be detectable.
- 02 / play
play
Every bet mixes the hidden server seed with a client seed you control and a nonce that counts your bets. The outcome is fixed by those three inputs.
- 03 / reveal
reveal
Rotate your seed pair and the old server seed is revealed. Hash it, compare it to the commitment, and recompute every result you played.
How provably fair works
Server seeds, client seeds, nonces, hashing and the commitment scheme that makes a result checkable after the fact.
cd /topics/how-it-works/ →Verification guides
Step-by-step walkthroughs for checking a specific result yourself, per game, with the code you need to do it.
cd /topics/verify/ →The original games
Crash, dice, plinko, mines, limbo, keno, towers and hi-lo — how each one is actually constructed and where its edge lives.
cd /topics/originals/ →Game maths
House edge, RTP, variance, expected value and the payout formulas that connect them.
cd /topics/math/ →Systems & bankroll
Why staking systems do what they do to your distribution of outcomes, and what risk of ruin actually looks like.
cd /topics/strategy/ →Everything, chronologically
ls -t /archive/ →10 articles so far, every one built on arithmetic you can check. Corrections to editor@provablyfairplay.com.