Trade risk and quantity tool
Position Size Calculator
Turn a chosen account-risk percentage and stop distance into a stock, crypto or forex position. Results are rounded down to the increment you enter so the planned loss does not exceed the calculated risk budget.
Position sizing result
Position size formula
Position sizing starts with a loss limit chosen before the trade. The calculator does not forecast the market and does not decide whether the risk percentage is suitable.
Price-based units = risk budget ÷ |entry price − stop price|
Forex lots = risk budget ÷ (stop pips × pip value per standard lot)
The raw result is rounded down to the entered unit or lot increment. Because of that rounding, the displayed planned loss should be equal to or lower than the risk budget.
Worked examples
Stock position example
A US$10,000 account with a 1% risk cap has a US$100 risk budget. An entry at US$50 and stop at US$48 create US$2 of risk per share. The raw position is 50 shares. A target at US$56 is US$6 above entry, so the estimated reward is US$300 and the reward-to-risk ratio is 3.00:1.
Forex position example
For the same US$10,000 account and 1% risk cap, a 50-pip stop with a pip value of US$10 per standard lot gives 0.20 lots: US$100 ÷ (50 × US$10). A 100-pip target represents a 2.00:1 reward-to-risk ratio and an estimated US$200 reward.
Fractional crypto example
With a US$5,000 account, 2% risk, entry at US$2,500, stop at US$2,400 and a 0.001-unit increment, the budget is US$100 and the position is 1.000 unit. The position value is US$2,500 and the planned stop loss is US$100 before fees or slippage.
How to use the result
| Result | Meaning |
|---|---|
| Risk budget | The selected percentage of the account balance expressed as money. |
| Position units or lots | The maximum rounded-down quantity under the simplified stop-loss model. |
| Planned loss | Quantity multiplied by price risk, or lots multiplied by stop pips and pip value. |
| Budget used | Planned loss as a percentage of the calculated budget; rounding normally keeps it at or below 100%. |
| Reward-to-risk | Target distance divided by stop distance. It is not a probability or expected return. |
Position sizing versus the Kelly criterion
This calculator begins with a risk percentage that you select, then converts it into a quantity using the stop distance. The Kelly Criterion Calculator starts with an estimated probability and payoff to derive a mathematical capital fraction. They answer different questions and should not be treated as interchangeable.
Limits and assumptions
- Balance ranges from 0.01 to 1 trillion; risk percentage ranges from 0.0001% to 100%.
- Price-based inputs must be positive and entry cannot equal the stop. A target, when entered, must be beyond entry in the trade direction implied by the stop.
- Forex mode requires the pip value for one standard lot in the account currency. Pip values vary by pair, price and account currency; this page does not fetch live exchange rates.
- The base-unit figure in forex mode uses the common reference of 100,000 base units per standard lot. Broker contract sizes can differ for metals, indices, CFDs and other instruments.
- All quantities are rounded down to the increment entered. If one increment already exceeds the risk budget, the calculator rejects the position instead of rounding up.
- Stops are execution instructions, not guarantees. Gaps, liquidity, spread, slippage and fees can increase the realized loss.
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