- Maths reviewed by Josh Miller
- Tested by Diana Westfield
A crypto dice calculator for the classic roll-over, roll-under game. Set a 49.5% win chance at a 1% house edge and the multiplier is exactly 2.00×: roll under 49.50 or over 50.50, and a 10p bet pays 20p back. Drop the chance to 10% and you get 9.9×. Push it to 98% and you get 1.0102×, a profit of about a penny on every pound. The CasinoCalcs calculator is free and also shows what a session costs you and how often losing streaks turn up.
How the crypto dice multiplier works
A dice game rolls a number from 0 to 99.99. You choose a target, and your win chance is the slice of the range on your side of it. A fair game would pay 100 ÷ chance. The house edge comes off the top: with 1% edge, it pays 99 ÷ chance.
| Win chance | Roll under | Multiplier (1% edge) | Profit on £1 |
|---|---|---|---|
| 98% | 98.00 | 1.0102× | £0.01 |
| 66% | 66.00 | 1.50× | £0.50 |
| 49.5% | 49.50 | 2.00× | £1.00 |
| 10% | 10.00 | 9.90× | £8.90 |
| 1% | 1.00 | 99.00× | £98.00 |
Roll over works the same way from the top end. 49.5% chance means rolling over 50.50. Some sites use a 0 to 100 range or round the targets a little differently. Check the win chance the game shows rather than the target number.
What a session really costs
The edge doesn’t care which chance you pick. You lose 1% of your total stake on average, every time. 1,000 rolls at 10p is £100 staked and an expected loss of £1. Fast auto-bet at 5 rolls a second gets through 1,000 rolls in about three minutes, which is why the total staked climbs much faster than it feels.
The swing is a different story. Those same 1,000 rolls at 49.5% have a standard deviation of about £3.16. So most sessions end anywhere from £4 down to £2 up, and the £1 average is buried underneath. At 1% win chance the swing is ten times wider. Bigger swings don’t mean better value, just a bumpier ride.
Losing streaks and doubling up
Doubling after every loss is the most common dice strategy, and long runs of losses are what break it. At 49.5%, 7 losses in a row happen about once every 119 tries. Starting at 10p, those 7 losses cost £12.70 and your next bet would be £12.80, all to win back 10p.
Over a long session, a run like that becomes likely. Set “Losing run to check” to the number of doubles your balance can survive and the calculator shows your chance of hitting it. The martingale calculator works through the stakes step by step, and the losing streak calculator handles any win chance.
If you want to check that a roll was fair, the provably fair calculator recomputes it from the seeds. To see what your stake is in pounds, use the crypto stake converter.
Limbo uses the same maths with a target multiplier: see the limbo calculator.
Auto-bet makes it easy to stake far more than you meant to. Set a loss limit before you start. BeGambleAware.org is free and confidential.