Legal

Provably Fair

Last updated: 3 October 2026

Every Tidebet original is decided by a published formula over three inputs: a server seed, your client seed and a nonce. Results are calculated on our server before any money moves, and you can check every round yourself once you rotate your seed.

1. The three inputs

• Server seed: a random 32-byte value (64 hex characters) created for your account and kept secret while it is in use. Only its SHA-256 hash is shown, which commits us to it in advance. When you rotate your seed, the old server seed is revealed and a new one starts.
• Client seed: a value you control. A random one is set for your account; you can change it (4 to 64 characters) in the "Provably fair" panel of any game. Changing it also rotates the server seed.
• Nonce: a counter on your account that goes up by one with every round on the current seed pair, so no two rounds use the same inputs.

2. From seeds to a result

For each round a digest is calculated:

digest = SHA-256( serverSeed | clientSeed | nonce | 0 | tidebet-v2 | gameId )

The game then reads numbers from that digest. Each number is 8 hex characters (a 32-bit value) taken from the digest at a given position, divided by 2³² to give a fraction between 0 and 1. Games that need several numbers (for example Plinko's 16 rows) read them from successive positions.

3. How each game uses the numbers

Dice

roll = floor(fraction × 10000) / 100, giving 0.00 to 99.99. The Dice page is a 50/50 bar: pick low or high. Payouts follow (1 − house edge) / win chance. The animation always lands on the fair roll.

Plinko

For each of the 16 rows, one fraction decides left or right (0.5 and above is right). The final slot sets the multiplier from the table for your chosen risk (low, medium or high). The ball is animated with real physics (Matter.js); small nudges on each peg keep it on the pre-decided path, so the physics never changes the result.

Blackjack

Each hand uses a fresh six-deck shoe. The round's digest (game id blackjack) is the shuffle seed for a Fisher-Yates shuffle of the shoe. The dealer stands on hard 17, hits soft 17, and blackjack pays 3:2.

Other originals

• Crash and Limbo: the multiplier is (1 − house edge) / (1 − fraction), rounded down to 2 decimals. Crash's curve grows with time on our server clock.
• Mines: mine positions are picked as unique tiles from successive fractions.
• Towers: the bomb column on each row comes from one fraction per row.
• Crossy Road: lane n has a car when its fraction is 0.8 or more (a 20% chance per hop), up to 15 lanes.
• Keno: 10 numbers are drawn from 1-40 with a partial Fisher-Yates draw.
• Roulette: the pocket index comes from one fraction (37 pockets European, 38 American).
• Slots: each reel picks a weighted symbol from a fraction.
• Coin Flip: a fraction below 0.5 is heads, otherwise tails.

4. House edge

5. How to verify a round

1. Open Provably fair · seeds & verify under any original game.
2. Play a round. The panel shows the server seed hash, your client seed, the nonce and the round digest.
3. Click Rotate seed (or change your client seed). The server seed you just used is revealed.
4. Click Verify last round. It checks that SHA-256 of the revealed server seed equals the hash shown before you played, and that recomputing the digest from the seeds and nonce gives the same digest.
5. You can also recompute the SHA-256 values yourself with any SHA-256 tool.

6. Good to know

Results are calculated and paid on our server; your browser only shows the animation. Because the active server seed stays secret until you rotate it, nobody can work out future results in advance, and because its hash is shown first, we cannot change it after you bet. Rounds you leave unfinished stay open on your account (Crash rounds settle on their own). A single round pays at most $10,000; see our Terms.

7. Questions

Email support@tidebet.fun.