Crash Mathematics — How the Multiplier and House Edge Actually Work
The exact formula behind a provably fair Crash game: how the crash point is derived from the hash, why the chance of reaching a multiplier is about 0.97/m, and why the house edge is the same at every cash-out.
From hash to crash point
Every round’s crash point comes from the provably fair hash (see how the hash is built ). Take the first 8 hex characters as an integer h — a uniformly random number between 0
and 2³² − 1 — and run the exact formula Lumenbet uses:
crash = max( 1 , min( (2³² / (h + 1)) × (1 − 0.03) , 1000 ) ) The 2³² / (h + 1) term creates the long tail of big multipliers; the × (1 − 0.03) applies the 3% house edge; the min(…, 1000) caps a round at 1000×; and the max(1, …) means a round can never pay less than 1.00×.
The distribution: chance of reaching m ≈ 0.97 / m
Because h is uniform, a short derivation shows the probability of reaching any multiplier m is:
P( crash ≥ m ) ≈ 0.97 / m So the further you push, the exponentially rarer it gets:
| Target multiplier | Chance of reaching it |
|---|---|
| 1.5× | 64.7% |
| 2× | 48.5% |
| 3× | 32.3% |
| 5× | 19.4% |
| 10× | 9.7% |
| 20× | 4.85% |
| 100× | 0.97% |
| 1000× | 0.097% |
The surprising part: the edge is the same everywhere
If you cash out at target c, you win c × your stake with probability 0.97 / c. Multiply them and the c cancels:
EV = c × (0.97 / c) = 0.97 Your expected return is 97% no matter what target you pick. Chasing 100× isn’t “riskier value” than cashing at 1.5× — both hand back 97 cents on the dollar on average. What changes is variance: a low target wins often and small, a high target wins rarely and huge. (See House Edge vs RTP for why edge and volatility are different things.)
Where the edge actually lands: instant crashes
That 3% has to show up somewhere concrete. It appears as the instant bust: roughly 3%
of rounds crash immediately at 1.00×, taking any bet that hadn’t already cashed out. Remove the × (1 − 0.03) and those instant crashes disappear — along with the house’s margin.
Verify any round yourself
None of this requires trust. Paste a round’s server seed, client seed and nonce into the verifier (choose Crash) and it recomputes the exact multiplier in your browser — the same formula above, running on the same hash.
Frequently asked questions
Is there a strategy that beats Crash?
No strategy changes the expected return. Every cash-out target has the same 97% RTP, so aiming for 2× or 100× gives the same average result — you only trade frequency for size. Auto-cashout systems and "martingale" staking change your variance, never your edge.
What are the odds of reaching 10×?
About 9.7%. The chance of reaching a multiplier m is approximately 0.97 / m, so 10× is 0.97/10 ≈ 9.7%.
Why does the game sometimes crash instantly at 1.00×?
That is the house edge made visible. Roughly 3% of rounds bust immediately at 1.00×, which is exactly the 3% edge expressed as a share of rounds.
Is the crash point decided fairly?
Yes. The crash point is derived deterministically from the provably fair hash and can be re-computed by anyone after the round. Nothing is chosen after you bet.