ℹ️ Educational Content: This article explains provably fair technology.
Provably fair means games are verifiably random—not that players will win.
Learn about responsible gambling.
What Is Provably Fair?
Provably fair is a cryptographic system that allows players to verify that casino game results are genuinely random and weren't manipulated by the operator.
Traditional casino games rely on third-party auditors to confirm fairness. Provably fair goes further—players can mathematically verify individual game results themselves.
The technology was pioneered by Bitcoin casinos in the early 2010s and is now used by major providers like Spribe (Aviator, Mines, Plinko).
How It Works (Technical)
Provably fair uses cryptographic hashing—the same technology that secures blockchain. Here's the typical process:
Step 1: Server Seed Generated
Before the round, the server creates a random "server seed" and shows you its hash (encrypted version). You can see the hash but not the actual seed.
Step 2: Client Seed Added
You (or the system) provide a "client seed"—random data that you control. This could be a random string or your choice.
Step 3: Combined Result
The game result is calculated by combining:
- Server seed (determined before you bet)
- Client seed (your input)
- Round number (nonce)
This combination produces the final result through a mathematical formula.
Step 4: Verification
After the round ends, the server reveals the original server seed. You can:
- Confirm the revealed seed matches the hash shown before
- Recalculate the result using server seed + client seed + nonce
- Verify the calculated result matches what was displayed
Why This Matters: The server cannot change the result after showing the hash.
If they changed the seed, the hash wouldn't match. Cryptographic hashing is one-way—
you can't fake a matching hash.
How to Verify Results
Most provably fair games offer verification tools:
- Find the game history in your account
- Locate the verification section (shows seeds and hashes)
- Copy the data to an independent verifier tool
- Recalculate the result and compare
Third-party verification tools exist online. You input the seeds and nonce, and they output what the result should be. If it matches, the game was fair.
What Provably Fair Guarantees
- True randomness: Results aren't predetermined based on your bet size
- No manipulation: The operator can't change results after you bet
- Transparency: You can verify any past result
- Independence: Each round is independently random
What Provably Fair Does NOT Guarantee
This is crucial to understand:
- Winning: Fair randomness doesn't mean you'll win—the house edge still applies
- RTP accuracy: The stated RTP is a statistical average, not a per-session guarantee
- Pattern prediction: Random results cannot be predicted or exploited
- Fairness of odds: The game can be provably fair while still having unfavorable odds
Critical Point: A provably fair game with 97% RTP will still cost you
~3% of your wagers over time. "Fair" means random and verifiable—not profitable.
The house edge is built into the multipliers and probabilities.
Games Using Provably Fair
Common provably fair games include:
- Aviator (Spribe) – crash game with 97% RTP
- Mines (Spribe) – minesweeper style
- Plinko (Spribe, BGaming) – ball drop
- Dice (Spribe) – simple high/low with 97% RTP
- HiLo (Spribe) – card guessing
- Keno (Spribe) – number selection
- Goal (Spribe) – penalty shootout theme
- Hotline (Spribe) – wheel game
- Mini Roulette (Spribe) – 13-number roulette
Traditional slots and live casino games typically use RNG certification rather than provably fair technology—they're audited by third parties like eCOGRA or iTech Labs.
Summary: Provably fair ensures the casino isn't cheating on individual results.
It doesn't change the fundamental mathematics—gambling still has a cost, and most players
lose over time. Use this technology to verify fairness, not to chase profits.