How to use it
Enter your entry, stop, and target prices. The calculator returns your reward-to-risk ratio, the risk and reward per share, and the breakeven win rate — the win percentage at which this setup neither gains nor loses over time. Add your typical win rate to see the expectancy in R, the average risk-units you'd make per trade.
Why the ratio alone isn't enough
A great reward-to-risk ratio doesn't guarantee profit — it has to be paired with how often you actually win. A 3:1 setup only needs a 25% win rate to break even; a 1:1 setup needs 50%. The breakeven win rate makes that trade-off explicit, and expectancy ties it all together: entry 100, stop 96, target 112 is 3:1, and at a 50% win rate that's +1.0R per trade in expectancy — a genuine edge.
The formulas
R:R = |target − entry| ÷ |entry − stop|,
breakeven win rate = 1 ÷ (1 + R:R), and
expectancy = winRate × R:R − (1 − winRate) (a loss counts as 1R).
TradeCaliper is a planning and education tool, not financial advice.