Provably Fair Checker: Verify a Round Yourself

This provably fair checker recomputes a Gift Club round from its seeds, in your browser, and shows you the result the server should have produced: the Plinko path, the Keno draw, the mine positions, the dice, the deck, and the exact payout. If the seed matches the hash you were shown before you played, the round could not have been changed after your bet.

How to verify a round

1. Before you play, open the game's Provably Fair panel and note the Server Seed Hash and your Client Seed. You can change the client seed to any letters, digits and hyphens you like.
2. Play your rounds. The first round on a seed uses nonce 0, the second nonce 1, and so on.
3. Tap Rotate Seed. The old server seed is revealed as Previous Seed (Revealed), and a new hidden seed takes its place. A seed is never revealed while you can still play with it.
4. Paste the four values above, choose the game and the settings you played with, and press Verify round.

The page loads with a worked example so you can see a passing check first. For a longer explanation of commit-reveal schemes, see provably fair verification.

What provably fair means

Before a round, the server commits to a secret seed by publishing its SHA-256 hash. The round's randomness comes from that seed combined with your client seed and a nonce. After you rotate, the server reveals the seed. If it hashes to the commitment, the server could not have swapped it once it saw your bet, and because your client seed is part of the input, it could not have picked a seed to suit you either.

Provably fair proves a round was not altered. It does not make a game a good bet: every game still has a house edge, published on its guide.

The algorithm this checker implements

Random bytes are HMAC-SHA256, keyed with the 32-byte server seed, over the text clientSeed:nonce:0, then :1, :2 and so on for more bytes. Every four bytes become one number between 0 and 1: the first byte divided by 256, plus the second divided by 256², and so on. Each game then uses those numbers in order:

• Plinko: one number per row; 0.5 or more bounces right. The slot is the count of rights.
• Keno: ten numbers shuffle the 40 tiles, and the first ten are drawn.
• Roll Over: the roll is the first number times 100, rounded down.
• Dice Duel: four numbers, each times 6 rounded down plus 1: your two dice, then the house's.
• Coin Flip: 0.5 or more is heads.
• Minefield and Mines Tower: one number per mine picks its tile from those still free.
• Balloon Pump: one number sets the pump the balloon bursts on.
• Higher / Lower: 51 numbers shuffle the 52-card deck before the first card is shown.

One more number after those settles a payout that is not a whole number of Stars: the payout rounds up when that number is below the fraction. Higher / Lower draws it from a separate stream with :payout added to the client seed. The checker applies the same rule, so the Stars it shows should match your history to the Star.

What this checker covers

It checks the draw for the nine games listed, whether the round was paid in Stars or TON. The payout line is for Stars rounds; TON payouts are not rounded with a random number, so for those, compare the draw and the multiplier. It implements Gift Club's algorithms only; other sites use their own, and seeds from them will not produce their results here.

Frequently asked questions