Provably Fair
What is provable fairness?
Provable fairness is a way of proving that every game result is truly random and free from manipulation. It’s a transparent and verifiable system — meaning you, the player, can mathematically verify the fairness of every bet.
To make sure everything runs honestly, Gambear uses a provably fair algorithm that lets you see exactly how each game result was generated. In short, you have full control and visibility over the randomness, so you can always trust the outcomes.
Every game on Gambear.com uses the same underlying method to generate random, verifiable numbers.
How it works
Each provable bet is generated using three main components:
- Client Seed (you control this)
- Server Seed (we provide this)
- Nonce (increments with each bet)
These values are combined and passed through a hashing function — HMAC_SHA256 — to create 32 random bytes (values between 0–255). The input message for HMAC is built like this:
client_seed:nonce:round
So for example, if your Client Seed is test1234, Nonce is nonce, and it’s the first round, the message will be:
test1234:nonce:0
Each time the 32 random bytes are used, the round value increases by 1.
Client Seed
This is your part of the equation — you can set any value or leave it blank. You’re also free to change it anytime, which creates a new chain of randomness. Since we don’t know your Client Seed in advance, we can’t rig the Server Seed to generate specific outcomes. This gives you full control and ensures the game is fair.
Server Seed
We generate this seed randomly as a 64-character hex string. Before you place any bets, you’ll be given a SHA-256 hash of the Server Seed — this way, the result is locked in and can’t be changed after the bet.
To view the actual Server Seed, just rotate it (trigger a new one). Once you do, you can verify that:
- The unencrypted Server Seed matches the hash you were shown earlier.
- The outcomes of bets made during that seed's active period are legit.
Nonce
The nonce is a number that increases by 1 with each bet. It ensures every bet has a unique input, even if the Client and Server Seeds remain the same.
How to Verify?
Step 1: Confirm the Server Seed hash
Use this tool and select the binary hash option.
For example, if your Server Seed is:
4babe5690cb4bba57a45267a7b0234ebfacb80ac231df6a9338c7d9cbf38e5b3
Its SHA-256 hash should be:
c153b4d6a284002dbbea66dbd36303997e5d02fd95b2913df944c09751d6f97a
This proves that the original Server Seed was pre-committed and unchanged.
Step 2: Generate the Result
Use a tool like this HMAC generator. Input the Server Seed as the secret key, and the message as:
client_seed:nonce:round
Example:
- Server Seed:
4babe... - Client Seed: (blank)
- Nonce:
57 - Round:
0 - Message:
:57:0
The resulting HMAC SHA-256 hash might look like:
e5593cf24c1ed1ba39c152738e74a67ee80a6c9829e3b0d68b9a51d2e87c3b36
🎲 Decoding the Dice Result
Let’s say you’re playing Dice. The game uses the first 4 bytes of the hash to generate a random float between 0 and 1.
Take the first 4 bytes: e5, 59, 3c, f2 — which are:
229, 89, 60, 242 (in decimals)
Now calculate:
229 / 256^1 + 89 / 256^2 + 60 / 256^3 + 242 / 256^4 ≈ 0.895893
Multiply this by 10001:
0.895893 × 10001 ≈ 8959.825
Round down to the nearest whole number → 8959
That’s the result of your Dice roll. 🎉
And yes, this is exactly what you would get in-game using the same inputs!
✅ Summary
- Every bet can be verified.
- You control the Client Seed.
- We commit to the Server Seed in advance.
- You can reproduce results using open tools.
- Transparency is baked into every single spin, roll, or flip.