Win rate calculator
Your win rate is only useful once you know how reliable it is and whether it is high enough for the size of your wins and losses. Enter your wins, losses and scratches, plus your average win and average loss, and this calculator gives your win rate, the range it probably falls in and the win rate you need to break even. It also shows how many more trades you need before the number can be trusted, and the losing streak you should be ready for.
Your win rate against break-even
Your measured win rate, the low and high ends of its likely range, and the win rate your average win and loss need.
How the range narrows with more trades
The same win rate measured over more trades. A range that sits fully above break-even means your edge is probably real.
| Trades counted | Low end | High end | Range width | Above break-even? |
|---|
How the win rate and its range are worked out
A win rate from a small sample can be far from your true long-run rate. The confidence range shows how far, using the Wilson method at 95 percent.
Win rate
Scratches are left out.
win rate = wins ÷ (wins + losses)
Confidence range
The Wilson interval, with z = 1.96 for 95 percent and n the number of wins plus losses.
centre ± z √(p(1−p)÷n + z²÷4n²), all ÷ (1 + z²÷n)
Break-even win rate
The win rate at which your average win and loss cancel out.
break-even = avg loss ÷ (avg win + avg loss)
Losing streak
The longest run of losses you should expect over 100 trades.
streak ≈ ln(100) ÷ ln(1 ÷ (1 − win rate))
Trades needed
Roughly how many trades give a range of about 5 points either side.
n ≈ 1.96² × p(1−p) ÷ 0.05²
Win rate questions
How do you calculate win rate?
Divide the number of winning trades by the number of trades that won or lost. With 26 wins and 34 losses, the win rate is 26 divided by 60, about 43 percent. Scratches, trades closed at roughly break-even, are usually left out so they do not drag the figure down.
What is a good win rate for trading?
There is no good win rate on its own. A trader who wins 35 percent of the time with winners three times the size of losers does well, while one who wins 70 percent of the time but loses big on the rest can still lose money. Compare your win rate with the break-even win rate your average win and loss imply.
How many trades do I need before my win rate means anything?
More than most people think. After 30 trades, a measured 50 percent win rate could easily be anything from about 33 to 67 percent. It takes a few hundred trades to narrow the range to a few points. The table below the calculator shows how the range shrinks.
What is the confidence range?
It is the range your true win rate probably falls in, given the trades so far. The calculator uses a 95 percent Wilson interval, which behaves well with small samples. If the whole range is above your break-even win rate, your edge is probably real.
How long a losing streak should I expect?
Longer than feels comfortable. With a 45 percent win rate, a run of 7 or 8 losses in a row is normal over a few hundred trades. Knowing that in advance helps you size positions so a streak does not knock you out.
Should I count partial wins?
Count a trade as a win if it closed in profit after fees, and a loss if it closed at a loss. Use average win and average loss to capture size. Scratches can be entered separately so they are tracked but not counted.