How does provably fair gaming work?

The problem provably fair solves

In a non-transparent casino, you have to trust the casino's word that every spin/dice/card outcome was random. With provably fair, you can mathematically verify every outcome — without trusting us.

How it works

For each game session:

1. We generate a server seed — a long random string. We hash it with SHA-256 and show you the hash before you start playing. This commits us to a specific server seed without revealing it.
2. You provide a client seed — generated by your browser, optionally editable by you.
3. A nonce (counter) increments with each bet you make: 1, 2, 3, …
4. Result formula: SHA-256(server_seed + ":" + client_seed + ":" + nonce) produces a deterministic hash. We map that hash to the game's outcome (a multiplier, dice value, card suit, etc.) using a published algorithm.

When the session ends, we reveal the original server seed. You can:

• Hash it yourself and confirm it matches the hash we showed at the start (proves we didn't change the seed mid-session)
• Re-run the formula with the revealed server seed + your client seed + each nonce
• Verify every result matches what was displayed

Verify a past round

Profile → Bet History → click any bet → click Verify. The verify widget shows:

• The (now-revealed) server seed
• Your client seed at the time
• The nonce of that bet
• The computed hash
• The mapped outcome

Match the displayed outcome to your bet history → proven fair.

You can also verify at the Provably Fair page by pasting any server seed + client seed + nonce.

Can the casino cheat?

Mathematically, no. To cheat, we'd have to:

1. Know your client seed in advance (we don't — you pick it)
2. Predict the SHA-256 output without computing it (impossible; SHA-256 is cryptographic-grade)
3. Or change the server seed mid-session (caught by the pre-published hash)

Which Cinoslots games are provably fair?

• ✅ All Originals (Crash, Plinko, Mines, Limbo, Dice, Hilo, Wheel, Keno, Roulette Original)
• ✅ Cinoslots-branded slots (a small handful with our internal RNG)
• ❌ Third-party slots (Pragmatic, NetEnt, Play'n GO etc.) — these use certified RNGs audited by iTech Labs / GLI / BMM instead. Same protection (you can't predict outcomes), different verification mechanism (third-party audit instead of self-verifiable cryptography).

Rotating seeds

You can rotate your server seed at any time from Profile → Provably Fair → Rotate seed. Doing so:

• Reveals the current server seed (so you can verify all past bets in the session)
• Generates a new server seed and shows you the new pre-hash
• Resets your nonce to 0

We recommend rotating after any large win for defense-in-depth.