Calculators
Every number shows the formula behind it, so the calculator teaches as it answers.
Position size
166 units
- Risk budget
- $250.00
- Risk per unit
- 1.50
- Actual risk
- $249.00
- Position value
- $8,300 (0.33× equity)
units = $250.00 ÷ 1.50 = 166.67 → rounded down
Reward-to-risk
2.40R · break-even win rate 29.4%
reward 12.00 ÷ risk 5.00 = 2.40R; break-even = 1 ÷ (1 + 2.40) = 29.4%
Expectancy and luck
The same edge, traded 100 times on 1,000 alternate timelines. The band holds 90% of outcomes; thin lines are single paths.
Expectancy +0.350R per trade · profit factor 1.64
- Median result
- 40.3%
- 5% worst / best
- 7.2% / 78.1%
- Chance of ending down
- 1.2%
- Median max drawdown
- 7.7%
- Chance of a 50% drawdown
- 0.0%
- Kelly fraction
- 17.5% (half-Kelly 8.8%)
Losing streaks and drawdowns
Expect a worst streak of about 6.0 losses in a row
| Losses in a row | Chance in 100 trades | Drawdown at 2% risk | Gain needed to recover |
|---|---|---|---|
| 3 | >99.9% | 5.9% | 6.2% |
| 5 | 81.0% | 9.6% | 10.6% |
| 7 | 31.8% | 13.2% | 15.2% |
| 10 | 4.4% | 18.3% | 22.4% |
A 50% win rate has better-than-even odds of six losses in a row somewhere in 100 trades. Size so that such a streak is survivable.