The mathematical expected result is an average across repeated comparable bets. It is not the result most people will necessarily experience in one sequence. The simulator therefore shows a range of possible balances, longest losing runs and drawdowns alongside the average.
A profitable assumption can still finish down
Even when the entered strike rate produces positive expected value at the entered odds, a finite run can lose. The probability estimate can also be wrong, which is a different and often larger risk than random variance.
| Output | Meaning | Limitation |
|---|---|---|
| Expected profit | Probability-weighted average across all entered bets | Depends entirely on the stated strike rate and price |
| 10th to 90th percentile | Middle 80% range of simulated ending balances | Outcomes can still fall outside this range |
| Longest losing run | Longest consecutive sequence of losses in each trial | Assumes independent bets with one fixed strike rate |
| Drawdown | Largest fall from a previous balance peak | Does not describe emotional or affordability impact |
For a direct comparison of flat, percentage and probability-based stakes, use the bankroll and unit-size calculator. The record-keeping guide explains how to gather the evidence needed for a credible strike-rate estimate.