What provably fair means on Shuffle
Shuffle’s provably fair system lets a player reconstruct a completed Original-game result from committed cryptographic inputs. It can show that the revealed server seed matches the pre-bet hash and that the recorded client seed and nonce reproduce the displayed result.
The operator commits to a hidden server seed by showing its SHA-256 hash before play. After the seed pair is rotated, the old server seed is revealed. Anyone can hash that revealed value and compare it with the earlier commitment.
The system makes individual rounds auditable without making future results predictable. It does not prove that gambling is profitable, remove the published house edge or verify third-party slots and live-dealer games through the same tool.
Server seed, client seed and nonce
A Shuffle Original result uses a hidden server seed, a player-visible client seed and a nonce that increments for each bet made with the same seed pair. Some games also use a cursor when they need more random values.
Shuffle’s implementation feeds the server seed into HMAC-SHA256 and updates it with the client seed, nonce and round cursor. The resulting bytes are converted into numbers between zero and one, then mapped to a game-specific event such as a Dice roll or Mines layout.
| Input | Purpose | When visible |
|---|---|---|
| Server-seed hash | Commits Shuffle to a hidden server seed | Before and during play |
| Revealed server seed | Lets the old commitment be checked | After rotating the seed pair |
| Client seed | Adds a player-controlled or browser-generated input | Visible and editable |
| Nonce | Creates a different result for each bet using the pair | Recorded with the bet |
| Cursor | Generates additional bytes for games needing several events | Used by the implementation |
How to verify a Shuffle round
Open a completed Original bet, rotate the active seed pair to reveal the old server seed, then use Shuffle’s Verify option with the recorded server seed, client seed and nonce. The reconstructed result should match the bet history.
Finish any active game before rotating the pair. Rotation creates new inputs for future bets and reveals the server seed used by the previous pair.
- 01Open the completed bet from the Original game or bet history.
- 02Record the bet identifier, client seed and nonce.
- 03Choose Rotate Pair and set the next client seed if prompted.
- 04Return to the old bet and copy the now-revealed server seed.
- 05Open Verify and enter the exact server seed, client seed and nonce.
- 06Compare the calculated event with the original result.
What does a successful verification prove?
A successful check proves that the disclosed inputs reproduce the recorded outcome and that the revealed server seed matches the earlier hash commitment. It does not prove that the payout table is favourable or that every other product on the site uses the same mechanism.
If the result does not match, first check for copied whitespace, the wrong nonce, a server seed from a different pair or a game-specific conversion rule. Save the raw inputs before contacting official support.
| Claim | Does verification establish it? | Why |
|---|---|---|
| The completed Original result matches the inputs | Yes | The calculation is reproducible |
| The server seed was not swapped after the bet | Yes, when the revealed seed matches the prior hash | SHA-256 commitment |
| The next result can be predicted | No | The active server seed remains hidden |
| The game has no house edge | No | Fair generation and payout mathematics are separate |
| Every third-party slot is verified this way | No | Provider RNG and certification systems differ |
Which Shuffle games use it?
Player-side provably fair verification applies to Shuffle Originals built in-house. Examples include Crash, Dice, Plinko, Mines, Slide, Limbo, Keno, Hilo, Blackjack, Baccarat and Roulette; the live lobby remains the source for the current lineup.
Game-event conversion differs by title. Dice maps a generated number to a 0.00–100.00 result, while Mines uses several values to place unique mines on a 25-tile board. Crash uses a separate published hash-chain design tied to a Bitcoin block hash.
Verification safety and dispute checklist
A verifier needs game seeds, not account credentials or wallet secrets. Do not paste a password, 2FA code, seed phrase or private key into a third-party fairness tool.
- Use Shuffle’s built-in verifier first
- Save the bet ID and exact inputs as plain text
- Confirm the old server-seed hash before rotation when possible
- Record the game title and rule configuration
- Contact official support if a reproducible mismatch remains