The ratio is the least interesting number here
Traders talk about risk-reward ratios as if a bigger number is better. It is not, and treating it that way is how a trader ends up with a book full of 5:1 setups that never reach their targets. The ratio tells you what you stand to make if the target is hit. It says nothing about how often that happens.
The number that decides whether a setup makes money is expectancy, and it needs both inputs.
Reward = |Target − Entry| × Multiplier × Contracts
Break-even win rate = Risk ÷ (Risk + Reward)
Expectancy = (Win rate × Reward) − (Loss rate × Risk)
Break-even win rate is the honest benchmark
Every trade carries an implied win rate below which it loses money. Inverting the ratio gives it to you exactly: a 3:1 setup needs 25 percent, a 2:1 needs 33.3 percent, a 1:1 needs 50 percent, and a 1:2 setup needs 66.7 percent.
This is why professional trend systems so often run win rates in the thirties and forties. They are not bad at predicting direction — they are deliberately taking setups where the target is far enough away that being right a minority of the time is enough. The ratio and the strike rate are two ends of the same lever.
What the calculation cannot tell you is whether your assumed strike rate is real. Use your own record, on your own instrument, on this specific setup. A win rate borrowed from a book or from a different market is an assumption, not an input.
Where a high ratio comes from, and what it costs
The ratio is not a free parameter. It is the consequence of two choices: how tight the stop is, and how far the target sits.
- Tighten the stop and the ratio improves, but the stop moves closer to the noise, so the win rate falls. Past a point the stop is inside the market's normal breathing and the setup becomes a coin flip with costs.
- Push the target further and the ratio improves, but the probability of reaching it falls. A target beyond the next obvious structural level is often a target that is never reached because price reverses there first.
Both levers trade one number for another. That is why the ratio alone is uninformative and the pair has to move together.
Costs are part of the ratio
Round-turn commission and expected slippage belong in the calculation, and on tight stops they are not a rounding error. If the cost is one tick and your stop is six ticks wide, you have silently widened your risk by roughly seventeen percent and narrowed your reward by the same, which shifts the break-even win rate by several percentage points.
The practical check: subtract cost from reward, add cost to risk, recompute expectancy. If the edge survives that, it is worth testing further. If it does not, you have saved yourself a live experiment.
Expectancy in R is the portable version
Expectancy in currency depends on how many contracts you traded and therefore on how big your account was. Expectancy in R does not. Dividing expectancy by risk gives the average result per unit risked, and that number travels across instruments, accounts and time.
A system with expectancy of 0.2R per trade makes twenty percent of one risk unit per trade on average. Over 200 trades that is forty risk units, which is a large return — provided the system survives the drawdown on the way there. A system with 0.02R is technically profitable and practically untradeable, because costs and variance will overwhelm forty basis points of edge.
The question the calculator forces
Because it asks for a win rate, this page does not let you evaluate a trade on the ratio alone. That is deliberate. A setup is only as good as the pair — ratio and strike rate — and any framework that looks at one without the other is describing half a trade.
If the expectancy is positive and comfortably above cost, the setup is worth taking repeatedly at a fixed risk. If it is positive but thin, it is worth paper-trading. If it is negative, no stop adjustment will rescue it, and the honest move is to skip the setup rather than to search for a version of it that fits a ratio target.