Under the hood · Seeds & verification
How Provably Fair Randomization Works
"Provably fair" isn't a marketing phrase — it's a specific mechanism. Here's how cryptographic seeds make a draw both genuinely random and independently verifiable.
The security explained simplyProvably fair sounds technical, but the core idea is simple and elegant: combine randomness that nobody can predict beforehand with a result anyone can reproduce afterward. Here's how the two halves fit together — no cryptography degree required.
Part one: unpredictable randomness
Every fair draw starts with a seed — a value produced by a cryptographically secure random source. Unlike a basic "pick a number" function, a crypto-secure generator produces values that can't feasibly be predicted or influenced. Because the seed is generated in the moment (on your own device, not a server), nobody — not even the breaker — knows the outcome before the draw runs.
Part two: deterministic replay
Here's the clever part. Once the seed exists, the draw is deterministic: the same seed and the same inputs always produce the exact same shuffle or race result. That sounds like it contradicts "random," but it doesn't — the seed itself was genuinely random and unpredictable. Determinism only kicks in after the seed exists, and that's precisely what makes verification possible.
How the pieces make a break tamper-proof
The seed is captured
The seed and inputs are encoded into a shareable replay link at the moment of the draw.
Anyone can replay
Opening the link re-runs the exact draw from that seed — same finish order, same pairing, every time.
Tampering is obvious
Change any input and the replay produces a different result than what was shown — so a doctored link simply won't match.
No server to trust
Because everything needed to verify is in the link, there's no database that could be quietly altered.
Why this beats "we use a good randomizer"
Plenty of tools use solid randomness. The gap is verifiability. A good RNG with no shareable, reproducible record still leaves a buyer taking your word for it. Provably fair closes that gap: the buyer doesn't trust the breaker, and doesn't even have to trust the tool — they can reproduce the math themselves. See it in practice in our provably fair breaks guide.
Run draws anyone can verify from the seed
Cryptographically fair, fully replayable, free to start — the security built in.
Open the free randomizer →FAQ
If a draw can be reproduced, is it still random?
Yes. The seed is generated with cryptographically secure randomness, so it's genuinely unpredictable before the draw. Reproducibility only applies afterward, once the seed exists — that's what enables verification.
Where does the seed come from?
A cryptographically secure random source on your own device, generated at the moment of the draw — not pre-decided or stored on a server.
Can the breaker fake a replay link?
No — changing any input changes the replayed result, so a faked link won't reproduce what was shown on stream.
Related: RNG for card breaks · Can a break be rigged? · How buyers verify a break