Trading Risk Calculator
Trade Direction
The table below shows what minimum win rate is needed to break even at each R:R ratio, before fees and slippage. These are mathematical thresholds, not profitability predictions.
| R:R Ratio | Win 1, Risk 1 | Break-Even Win Rate | Win for 10 Trades |
|---|---|---|---|
| 1:0.5 | $0.50 per $1 risked | 66.7% | Need 7 wins |
| 1:1 | $1.00 per $1 risked | 50.0% | Need 5 wins |
| 1:1.5 | $1.50 per $1 risked | 40.0% | Need 4 wins |
| 1:2 | $2.00 per $1 risked | 33.3% | Need 4 wins |
| 1:2.5 | $2.50 per $1 risked | 28.6% | Need 3 wins |
| 1:3 | $3.00 per $1 risked | 25.0% | Need 3 wins |
| 1:4 | $4.00 per $1 risked | 20.0% | Need 2 wins |
| 1:5 | $5.00 per $1 risked | 16.7% | Need 2 wins |
Use the Position Size tab to enter your trade details, then return here to see the full step-by-step calculation.
What Is a Risk Calculator?
In trading, a risk calculator converts your account size and planned risk percentage into a specific position size, dollar risk amount, and potential profit based on your entry price, stop-loss, and target. It answers three questions at once: how much am I risking, how many units should I buy or sell, and what could I make if the trade works out.
The word "risk calculator" carries different meanings across domains. Health risk calculators estimate disease probability from clinical variables. Insurance risk tools price premiums from actuarial tables. Portfolio risk models measure volatility and correlation. Search volume data consistently points to trading as the primary intent for the bare phrase — so this page focuses on the trade setup model. If you arrived looking for something else, the links at the bottom connect to relevant statistics tools on this site.
The arithmetic here does not change regardless of what you trade. The same formula applies to stocks, ETFs, spot forex, and spot crypto. What changes with derivatives, futures, and CFDs is the contract structure — tick value, lot size, multiplier — which the basic calculator does not handle. For those instruments, you need contract-specific inputs beyond what is covered here.
Trading Risk Formulas
Four formulas drive every result in this calculator. Risk amount comes from the account. Position size comes from dividing risk amount by stop distance. Position value is size times entry price. Risk/reward compares how far the target is from entry versus how far the stop is.
Risk Amount
Risk = Account × Risk%
Example:
$10,000 × 1%
= $100 at risk
Position Size
Size = Risk ÷ |Entry - Stop|
Example:
$100 ÷ $5
= 20 shares
Position Value (Exposure)
Value = Size × Entry Price
Example:
20 × $100
= $2,000 exposure
Risk/Reward Ratio
R:R = |Target - Entry|
÷ |Entry - Stop|
Example:
$10 ÷ $5 = 2
→ 1:2 ratio (or 2R)
The position size formula has one consequence worth writing out explicitly: a wider stop on the same risk budget forces a smaller position. If your risk is $100 and the stop is $2 away, you can hold 50 units. If the stop is $10 away, you can only hold 10 units. Wider stops are not automatically bad, but they cost you position size, which changes how the trade behaves. The probability calculator on this site can help you think about the likelihood of different price levels being reached.
How to Use This Risk Calculator
Enter your account balance, set a risk percentage, choose long or short, input an entry price and a stop-loss, and optionally a take-profit target. The calculator gives position size, dollar risk, potential profit, and risk/reward ratio in one step.
Use the balance you are actively trading, not a paper or theoretical figure. The risk amount scales directly from this number, so accuracy matters. For a $10,000 account, even small percentage differences change the dollar risk noticeably.
This is the slice of your account you are willing to lose on this trade if the stop fills. The calculator applies whatever percentage you enter; it does not recommend one. Common ranges traders use run from 0.25% to 2%, but that depends entirely on strategy, volatility, and personal tolerance.
Select Long if you are buying with the expectation of price rising, or Short if you are selling with the expectation of price falling. The calculator validates that your stop is on the correct side of entry and will show an error if the relationship is wrong.
For a long, the stop should sit below entry. For a short, above it. The distance between them determines your risk per unit. A long with entry at $100 and stop at $95 has $5 risk per share, so the calculator divides your dollar risk budget by $5 to get position size.
If you have a target, enter it to get the R:R ratio and potential profit in dollar terms. You can skip this field to focus on sizing alone. For a long, the target should be above entry; for a short, below it. The calculator flags mismatches.
Scan the Position Value (Exposure) field alongside the risk amount. A $100 risk on a $2,000 position means 20% of the account is in the trade but only 1% is at risk. Knowing both numbers gives a clearer picture than risk percentage alone.
Worked example (Long): Account $10,000 • Risk 1% • Entry $100 • Stop $95 • Target $110. Result: Risk Amount = $100, Risk/Unit = $5, Position = 20 shares, Position Value = $2,000, Potential Profit = $200, R:R = 1:2. Try it with the "Example: Long Trade" button above.
Long vs. Short: What Changes in the Calculation
The position size formula is identical in both directions. What changes is where the stop and target sit relative to entry, and which direction a gap would hurt you.
Table: Long vs. Short Trade Setup Comparison
| Field | Long (Buy) | Short (Sell) |
|---|---|---|
| Direction | Expecting price to rise | Expecting price to fall |
| Stop-Loss Position | Below entry price | Above entry price |
| Take-Profit Position | Above entry price | Below entry price |
| Risk Per Unit | Entry − Stop | Stop − Entry |
| Reward Per Unit | Target − Entry | Entry − Target |
| Gap Risk Direction | Downward gap past stop hurts | Upward gap past stop hurts |
| Example Setup | Entry $100, Stop $95, Target $110 | Entry $100, Stop $105, Target $90 |
| Risk Per Unit (Example) | $5 | $5 |
| R:R (Example, 1% risk) | 1:2 — 20 shares, +$200 potential | 1:2 — 20 shares, +$200 potential |
Risk vs. Exposure: Not the Same Number
Risk is how much you lose if the stop fills. Exposure is the total notional value of the position. Confusing the two is one of the most common errors new traders make, and it can lead to overleveraged positions that look fine on a percentage basis until something goes wrong at the market level.
On a $10,000 account holding 20 shares at $100, the position value is $2,000 — 20% of the account in one trade. But if the stop is $5 below entry, the actual risk is only $100, or 1% of the account. Both numbers matter. A trader might set a disciplined 1% risk on every trade but still end up with 50% of their capital concentrated in a single sector if several positions each carry 15–20% exposure. The probability that a sector-wide event moves all those positions simultaneously is not captured by the individual trade risk figure.
Run a calculation above to populate this waterfall.
📊 How Stop Distance Affects Position Size
With a fixed $100 risk budget, moving the stop further away shrinks the position. Moving it closer expands it. Neither approach is better — the right stop distance comes from the trade setup itself, not from trying to hit a specific position size. But the table below makes the trade-off concrete.
Table: Position Size by Stop Distance ($100 Risk Budget)
| Stop Distance | Stop % (from $100 entry) | Position Size | Position Value ($100 entry) |
|---|---|---|---|
| $0.50 | 0.5% | 200 shares | $20,000 |
| $1.00 | 1.0% | 100 shares | $10,000 |
| $2.00 | 2.0% | 50 shares | $5,000 |
| $5.00 | 5.0% | 20 shares | $2,000 |
| $10.00 | 10.0% | 10 shares | $1,000 |
| $20.00 | 20.0% | 5 shares | $500 |
| $50.00 | 50.0% | 2 shares | $200 |
Notice what happens to position value as the stop widens. At a $0.50 stop, the $100 risk budget buys a $20,000 position — on a $10,000 account, that is 2x leverage even though the stated risk is 1%. Tight stops are not safer in that sense; they concentrate more capital in fewer price points.
Seven Calculation Mistakes That Change Your Risk
Fixed share counts ignore the fact that a wider stop on the same account increases actual dollar risk. Two trades with the same 100-share size but different stop distances carry very different risk amounts.
A $2,000 position does not mean $2,000 at risk. Only the distance from entry to stop, multiplied by position size, equals your risk amount.
Rounding 18.7 shares to 19 slightly exceeds your planned risk budget. The calculator shows both the exact and whole-unit figures. When risk management is the goal, round down.
On a tight-stop trade, a $0.05 spread on a 200-share position adds $10 to the cost of entry, which comes straight out of the $100 risk budget before the trade even moves.
A stop order triggers a market order when the stop price is reached. In fast markets or on gap opens, the fill price can be well past the stop. This calculator assumes exact fill at the stop unless you account for slippage manually.
A 1:3 R:R setup loses money if you win fewer than 25% of trades. R:R and win rate interact; neither tells the full story on its own.
Futures and some CFDs have a tick value or contract multiplier that the basic position size formula does not account for. Applying a spot-style calculation to a contract with a $50 per tick value will produce the wrong position size.
Risk Management and Statistical Thinking
The tools on this site are primarily about statistical inference, but risk management in trading draws on the same underlying ideas. Expected value connects directly to trading expectancy: average win multiplied by win rate, minus average loss multiplied by loss rate. A positive expectancy is the statistical equivalent of having an edge.
Probability rules apply to consecutive trade sequences. The chance of hitting a six-loss streak at 40% loss rate is roughly 4.7%, which sounds unlikely until you trade 200 times. The statistics in risk management article on this site covers the formal connections between statistical concepts and financial risk models, including Value at Risk.
Related Tools and Guides on Statistics Fundamentals
These calculators and guides connect directly to the probability and statistics concepts behind trading risk management.
Frequently Asked Questions
A trading risk calculator computes the position size, dollar risk amount, stop-loss distance, potential profit, and risk/reward ratio from your account size, risk percentage, entry price, stop-loss, and take-profit. It converts your planned risk budget into a specific number of units or shares to trade.
Position Size = Risk Amount ÷ Risk Per Unit. First calculate Risk Amount = Account Size × Risk%. Then calculate Risk Per Unit = |Entry Price − Stop-Loss Price|. Divide the first by the second. For example: $10,000 account at 1% risk = $100 risk amount. Entry $100, stop $95 = $5 risk per unit. Position size = 100 ÷ 5 = 20 shares.
Risk per trade is the dollar amount you plan to lose if price hits your stop. It equals Account Size × Risk%. What percentage to use depends on your strategy, the volatility of the market, your win rate, and how many consecutive losses your account can survive. This calculator applies the percentage you enter; it does not recommend one.
Risk/reward ratio compares potential profit to planned risk: R:R = |Target − Entry| ÷ |Entry − Stop|. A trade with $5 risk per unit and $10 reward per unit has a 1:2 ratio. A higher ratio does not guarantee profitability — that depends on your actual win rate. The break-even win rate at 1:2 is 33.3%; you need to win more than that to have a positive expected return.
No. A stop-loss triggers an exit order when the stop price is reached, but the fill price can differ from the trigger price. Common causes include market gaps (price opens beyond the stop), fast-market conditions where liquidity is thin, spread on the instrument, and slippage from order type. The calculator assumes the stop fills exactly at the entered price.
1R is the planned dollar risk on a trade. If you risk $100, then 1R = $100. A trade that wins $200 returns +2R. A trade that hits the stop at the planned price returns −1R. R-multiples let you compare outcomes across trades of different dollar sizes. A $200 win on a $100-risk trade and a $2,000 win on a $1,000-risk trade are both +2R, even though the raw dollar amounts differ.
Risk is the amount you lose if the stop fills at the planned price. Exposure is the total notional value of the position (Size × Entry Price). On a $10,000 account: a 20-share position at $100 has $2,000 exposure (20% of account) but only $100 risk (1% of account) if the stop is $5 away. Both matter. High exposure relative to account size means a large adverse move — beyond the stop — can damage the account more than the risk percentage suggests.
Wider stops mean smaller positions when the risk budget is fixed. Risk Budget $100 ÷ $2 stop distance = 50 shares. $100 ÷ $10 stop distance = 10 shares. The stop distance should come from the trade setup — support levels, volatility, chart structure — not from reverse-engineering a desired position size.
The core arithmetic works for any instrument where position size is in discrete units. For spot forex quoted directly in your account currency and spot crypto, the formula applies directly. For forex with cross-currency conversion, leverage, or lot structure, and for futures with tick values and contract multipliers, you need contract-specific inputs beyond what this calculator covers.
Break-even win rate is the minimum percentage of winning trades needed to avoid a net loss at a given R:R ratio, before costs: Win Rate = 1 ÷ (1 + R:R). At 1:2 R:R, that is 1 ÷ 3 = 33.3%. Earn more than 33.3% wins at this ratio and you have a positive theoretical edge; earn less and you lose money over time. It matters because a high R:R ratio does not guarantee profitability if the actual win rate falls below the break-even threshold.