In the world of crypto gambling, trust is good, but verification is better. Provably Fair is a technology that makes it impossible for a casino to cheat you without getting caught.
Our Provably Fair Verifier uses the industry-standard HMAC-SHA256 algorithm. By entering the seeds provided by the casino, you can independently generate the result hash and confirm that it matches the game outcome.
Standard HMAC-SHA256 verification.
How to Use the Verifier
To verify a bet, you usually need to open the “Bet Details” or “Fairness” tab on the casino website.
- Server Seed: This is the secret key generated by the casino. You only see the Unashed version after the seed pair changes (or after you reveal it).
- Client Seed: This is the key you chose (or the random string assigned to your browser).
- Nonce: The bet number in your current session (e.g., 1, 2, 3…).
- Verify: Click the button. The tool will generate a Result Hash (Hex).
- Compare this Hash with the one shown on the casino website. If they match exactly, the game was fair.
Example: Verifying a Bet
Most crypto casinos (like Stake or PrimeDice) use the following logic:
Result = HMAC_SHA256(Server_Seed, Client_Seed + Nonce)
- Server Seed:
a1b2c3...(The casino’s secret) - Client Seed:
myLuckySeed(Your input) - Nonce:
5(The 5th bet)
If the casino claims the Result Hash was f4e3..., you can put these three values into our tool. If our tool also outputs f4e3..., it proves mathematically that the casino decided the result before you placed the bet and did not change it based on your stake.
Frequently Asked Questions (FAQ)
What is Provably Fair?
It is a cryptographic method that ensures neither the casino nor the player can know the result of a game beforehand, but the player can verify after the game that the result was generated fairly.
Why do I need the “Unhashed” Server Seed?
While playing, you only see the hashed version (encrypted) of the Server Seed. This proves the casino committed to a result. To verify the calculation, you need the unhashed (revealed) seed, which is usually shown when you rotate your seed pair or reset your randomness.
Does this tool check the Roll number (e.g., 98.5)?
This tool calculates the Result Hash. Different games (Dice, Roulette, Slots) use different formulas to convert this Hash into a number (e.g., converting the first 4 bytes to a float). Since every game is unique, we provide the raw Hash, which is the foundation of verification.