Don't trust us. Recompute it.

The two guarantees

Provable fairness rests on two properties, and REDLINE delivers both:

• Commit and reveal. The operator commits to an outcome by publishing its hash before any bet is placed, then reveals the secret after the round. The outcome cannot be changed after the fact without breaking SHA-256.
• Fixed house edge. The crash multiplier is drawn from a distribution where the expected return of cashing out at any target equals one minus the house edge. No strategy beats it, and the operator cannot beat the math either.

The crash formula

For a round with secret seed and a public salt, the crash multiplier is a pure function:

Because the return to player is identical for every target, no cash-out point and no bet size can beat the declared edge. At a 3% edge that is a fixed 97% RTP, and it is configurable per operator.

The pre-committed hash chain

REDLINE does not commit one round at a time. It commits to tens of thousands of rounds at once. A secret tail seed is hashed repeatedly to build a chain, and the chain is consumed in reverse so each revealed seed hashes to the previously revealed one. The single published chain commitment seals every future outcome before play begins. The operator cannot insert, drop, or reorder a result anywhere in the chain.

The public beacon, against grinding

A hash chain alone proves the operator cannot change a committed outcome, but on its own it does not stop the operator from generating many chains and keeping a favourable one. REDLINE salts every round with a public randomness beacon (a value from the drand network) that did not exist when the chain was committed. Because the operator commits first and the beacon is only known later, it cannot have ground the chain against it. If the beacon is ever unavailable, REDLINE degrades to a deterministic value derived from the committed chain, never to operator-chosen randomness, and records which source was used.

Verify any round yourself

After every round the secret seed is published. To verify a result:

1. Take the revealed seed and the round's public salt, edge, and max multiplier.
2. Compute U = HMAC_SHA256(seed, "crash:"+salt) and take its top 52 bits over 2⁵².
3. Compute crash = floor((1 - edge) / U), floored to 0.01x and capped at the max.
4. Confirm SHA256(seed) equals the commitment published before the round, and that it chains to the next round.

The result is exact and reproducible on any machine. We publish an in-browser verifier that does this for you, and an offline lab kit that reproduces the full distribution over a hundred million rounds against the same code the live game runs.