Fair play: how to verify every round

On IS Casino every result comes from a verifiable cryptographic generator (provably fair): the SHA-256 hash of the server seed is published before the round, the seed is revealed after, and you can recompute the result in your browser and compare.

Updated October 17, 2026

The idea in one sentence

The server commits to the result before you play (by publishing the seed hash) and cannot change it afterwards, because any change to the seed would change the hash.

The ingredients

Server seed: the server’s secret; its SHA-256 hash is shown first.
Client seed: yours, editable on the in-app Fair play page; it stops the server from choosing the result alone.
Nonce: the round number under that seed pair.
Formula: result = HMAC-SHA256(server seed, “client seed:nonce:game”), mapped to the game outcome.

Step by step (slots and instant games)

Before playing, note the server seed hash shown in the game and, if you like, change your client seed.
Play as usual; each round uses the next nonce.
Rotate the seed pair: the old server seed is revealed.
On the in-app Fair play page, paste the revealed seed, your client seed and the nonce: the result is recomputed in the browser. Also check that SHA-256(revealed seed) equals the hash you noted.

By game type

Slots: Each spin is one pre-computed outcome (spin, cascades, respins and free spins together), selected by HMAC-SHA256 of the server seed with your client seed and the round number (nonce). The server seed hash is shown first; when you rotate the seed pair the old seed is revealed and you recompute the spin on the Fair play page.
Crash games: The crash point is fixed before the round starts and its hash is published. After the round the key is revealed and anyone can recompute the result. Formula: the chance of reaching ×x is RTP ÷ x.
Live tables and game shows: The round seed hash is published before choices close; after the round the seed is revealed and the result (cards, dice, number or tile) is recomputed in your browser.
Instant games: Result = HMAC-SHA256(server seed, “client seed:nonce:game”). The server seed hash is shown first; rotate the seed pair to reveal the old seed and recompute the round on the Fair play page.
Bingo: Before card sales open, the SHA-256 hash of the round seed is published. The ball order comes from that seed and your cards from your client seed. After the draw the seed is revealed so you can check it.
Poker: Before each hand the server publishes the hash of its secret seed. The deck is shuffled (Fisher–Yates) with the server seed plus every seated player’s client seed; 10 minutes after the hand the participants get the seed and recompute the deck in the browser.

Full explanation, with examples of how the HMAC becomes a result: what provably fair is and how to verify a round.

RTP never changes the draw

The club can adjust a game’s RTP (between 80% and 99%). That only changes the published payouts (the formula or the multipliers), never how the result is generated, applies to everyone from the next round, and every round records the RTP it was opened with. See the RTP table.

AI and house players

When few people are online, AI players join poker tables and some rooms; they follow the same rules and never see anyone’s cards. Live tables, rooms and crash games may include house players: their stakes are not paid and do not affect anyone’s result or payouts. In Bingo they buy cards with house chips and play on equal terms.