Casino Technology

Provably Fair: how to verify crypto game fairness

Provably Fair lets any player mathematically verify that a game result was not manipulated. Here's how it works.

🔄 Updated July 9, 2026

Provably Fair is one of the major innovations of crypto casinos. It allows any player to independently verify that game results are fair — without having to blindly trust the casino.

The problem it solves

In a traditional or classic online casino, you must trust the casino: trust that the RNG isn't manipulated, that the regulatory authority's audit is rigorous, and that the casino isn't cheating specific players. Provably Fair eliminates this need for trust.

How Provably Fair works

Before the round: the casino generates a "server seed" and shares its cryptographic hash with you. You provide your own "client seed".
During the round: the result is generated from the combination of server seed + client seed + round number.
After the round: the casino reveals the original server seed. You can then recalculate the result yourself and confirm it matches what was played.

If the casino had manipulated the result, its server seed would not match the hash shared before the round — fraud would be immediately detectable.

Which games are Provably Fair on Stake?

All Stake Originals are provably fair: Crash, Dice, Mines, Limbo, Plinko, Keno, Wheel, Hilo and Diamonds. Third-party games (slots, live casino) are not provably fair — they use RNGs certified by external auditors.

How to verify on Stake

On Stake, every bet has a "Fairness" button accessible from the bet history. Click it to access the seeds and the integrated verification calculator. You can also use independent online verifiers by entering the seeds and result.

Play Provably Fair games

Crash, Mines, Dice, Limbo — all Stake Originals are verifiable. Register on Stake to access them.

Registration guide →

Also see: Crash strategy, Mines strategy, Stake full review.

Frequently asked questions

What does provably fair mean?

Provably fair means a game's outcome can be mathematically verified by the player after the fact, using cryptographic hashes exchanged before and after the round. It removes the need to simply trust the casino — you can check the math yourself.

How do I verify provably fair on Stake?

Open the "Fairness" panel from your bet history, which shows the server seed, client seed and nonce for that round. Enter these into the built-in calculator (or an independent third-party verifier) to recalculate the result and confirm it matches what was played.

Is a "provably fair predictor" tool real?

No — "predictor" tools claiming to forecast the outcome of a provably fair game before it happens are scams. By design, the server seed that determines the result isn't revealed until after the round, so no external tool can predict it in advance. Any site or app selling a "Crash predictor" or "Mines predictor" is misleading players — provably fair guarantees verifiability after the fact, not predictability before it.