The algorithm determines results in a manner similar to a regular random number generator, but with added cryptographic proof. Instead of just trusting the casino, players get access to the underlying data that determines each result.

Unlike what the name might suggest, most provably fair systems don’t run on the blockchain. While they use blockchain-style cryptography, the actual game data (like hashes and seeds) is typically stored on centralized systems.

At the end of a spin/round/turn, players gain access to those records and can verify that their results were random.

How Provably Fair Games Work

Here’s how it works:

The Role of the Server Seed

Before you place a bet, the casino generates a hidden string of characters (the server seed). This seed is hashed and shown to you, so you know it won’t change later.
Client Seed and Player Interaction

Either you choose your own client seed, or the casino gives you one. This adds a layer of randomness that the casino can’t control.
The Nonce for Unique Results

The nonce (a counter) increases with every bet. Even if you use the same seeds, your results stay unique each time.
Combining Seeds and Nonce for Fair Outcomes

These three inputs are run through a cryptographic function to generate the outcome of each bet.
You verify the result:

Once you close the game, the casino reveals the original server seed. You can put that seed through a verification tool to confirm your outcomes were random and legitimate.