Provably Fair CheckerSHA-256

Duel Provably Fair Verifier

Duel, the games engine behind Duelbits, uses a plain SHA-256 construction with its own message format: serverSeed:publicSeed:nonce. Duel Dice is fully reproducible here byte-for-byte; Duelbits publishes only limited reference code for its other games, so this hub is transparent about what it can and can't independently verify.

6 games at Duel

Seed pair

Client seed

Server seed (unhashed)

Nonce

Runs entirely in your browser - your seeds never leave this device.

Roll Result

00.00

0255075100

Provably fair verification lets anyone independently recompute a game's result from its server seed, client seed and nonce - confirming the casino could not have altered the outcome after the bet. Browse all casinos & games

How Duel provably fair works

Duel hashes the message serverSeed:publicSeed:nonce with plain SHA-256 - the 'public seed' plays the role other casinos call the client seed. There is no HMAC keying step.

For Dice, Duel reads the first eight hex characters of that hash, parses them as an integer, and reduces modulo 10000 then divides by 100 to produce a 0.00-99.99 roll. The verifier above implements that exact calculation, so Duel Dice matches your bet history precisely.

Duel commits to the server seed before the bet via its hash, so a result can't be changed after you play. Reveal the server seed by rotating seeds to confirm a past Dice round here.

Duel's provably-fair games

Duel Dice is byte-verifiable above. Duelbits' other games - Mines, Plinko, Keno, Blackjack and Crash - render in the selector for reference, but Duelbits does not publish complete verification code or a live checker for them, so this hub does not claim to reproduce them independently. We would rather be accurate than overstate coverage.

How to verify a Duel result

1Open the Provably Fair or Fairness settings in your Duelbits account.
2Rotate your seed pair to reveal the previous server seed unhashed.
3Copy the server seed, your public (client) seed and the nonce.
4Paste them above with Dice selected to reproduce the roll.

Duel provably fair FAQ

What algorithm does Duel use?⌄

Plain SHA-256 over the message serverSeed:publicSeed:nonce, with no HMAC. Duel Dice takes the first eight hex characters, reads them as an integer, and computes value modulo 10000 divided by 100 for the 0.00-99.99 roll.

Which Duel games can I verify here?⌄

Dice is fully reproducible byte-for-byte. Duelbits publishes only partial reference code for its other games and offers no public verifier for them, so we don't claim to reproduce Mines, Plinko, Keno, Blackjack or Crash independently.

Is Duelbits provably fair?⌄

Its Dice game is committed to a hashed server seed and independently checkable here. For the rest, fairness rests on Duelbits' own commitment scheme, which this tool can't fully re-derive without complete published code.

What is the public seed on Duel?⌄

It is Duel's name for the client-side seed in the hash - the message is serverSeed:publicSeed:nonce. Paste your public seed in the client-seed field above to verify a Dice roll.