Risk/reward ratio: why you should count R before entering a trade

The risk/reward ratio shows how much potential gain you are aiming for relative to the amount you can lose. When you calculate it before opening a position, your entry decision becomes measurable instead of based on feeling. Below are the core logic, a worked example, and the limits of the method.

What R is and why it helps

In trading, R is the amount you are willing to lose on a single trade. It is a predefined risk on one idea, not the size of the whole position.

• R can be set in money or as a percentage of your capital, for example 1%.
• Results are easier to compare when expressed in R: a loss equal to your risk is -1R, and a gain three times that size is +3R.
• This language lets you compare trades of different sizes and different instruments.

How the ratio is calculated

You need three values: the entry price, the stop-loss price (where your idea is proven wrong), and the target (where you plan to take profit).

• Risk per unit is the distance between entry and stop.
• Reward per unit is the distance between target and entry.
• The ratio is reward divided by risk.

A hypothetical example

Suppose your account is $10,000 and you risk 1% per trade, which is $100 (1R). A hypothetical asset trades at 100, with a stop at 98 and a target at 106.

• Risk per unit: 100 − 98 = 2.
• Reward per unit: 106 − 100 = 6.
• Ratio: 6 / 2 = 1:3.
• Position size: $100 / 2 = 50 units.
• If the target is hit, the result is about +$300, or +3R. If the stop is hit, the loss is about $100, or -1R.

These numbers are illustrative only. A real market can gap through a stop, and execution may differ from your plan.

Why count before entering

After you enter, emotions distort your judgment. Traders often move a stop to "give the price room" or shift a target to feel more comfortable. Calculating before entry locks in the conditions you agreed to in advance.

• Before entry, you can see whether the trade is worth its risk and skip it if it is not.
• Position size follows from the stop, not from a wish to earn more.
• A journal kept in R shows how your strategy actually performs.

Limits of the approach

A high ratio does not guarantee success. It links risk to target but says nothing about how often the target is reached.

• At 1:2, breaking even before costs requires winning roughly one trade in three. At 1:1, it requires about half, excluding fees and slippage.
• Targets that are too far away are reached less often, so a strategy can look good only on paper.
• Stops that are too tight get triggered by normal volatility before your idea has time to play out.
• Most beginners lose money, and a formal R calculation alone does not fix that.

What it means for traders

• Define your risk per trade in R before opening a position, and respect that limit.
• Calculate the risk/reward ratio for every idea and skip trades where the target is small relative to the stop.
• Derive position size from the stop: set the stop first, then the volume.
• Do not move a stop further from entry to rescue a losing trade.
• Keep a journal in R and judge your strategy over a series of trades, not one result.
• Remember that the ratio describes a trade's structure, not its probability of success. Trading involves risk, and losses are part of it even when R is handled correctly.