Position Size Calculator
Calculate the number of units to trade given your account balance, the percentage of capital you're willing to risk, and the distance between entry and stop-loss.
INPUTS
RESULTS
Method and assumptions
Risk amount = account balance × risk % / 100. Position units = risk amount / |entry − stop|. Notional = units × entry. This tool uses a unit value of 1 in the same currency as the account; use the ATR tool's explicit value field for other contracts.
Common mistakes and edge cases
Entry and stop cannot match. Use positive prices and risk no greater than 100%. A theoretical fractional size must be rounded down to a valid lot size. Fees, gaps, slippage, leverage and FX conversion are not included.
How to use
- Enter your total account balance.
- Enter the percentage of capital you're willing to risk on this trade.
- Enter your intended entry and stop-loss prices.
- Position size, risk amount, and notional exposure are calculated instantly.
Example
With a 10,000 balance, 1% risk, entry 100 and stop 98, risk is 100, stop distance is 2, size is 50 units and notional is 5,000.
Frequently asked questions
- What does risk percentage mean?
- The share of your account balance you're prepared to lose if the trade hits the stop-loss.
- Does this include fees?
- No. Fees, spread, slippage, and swap costs are not modelled — factor them in separately.
- Is my data stored?
- No. All calculations happen in your browser and nothing is transmitted.
RELATED TOOLS
- Risk-to-Reward Calculator
Compute risk-to-reward ratios and break-even win rate.
- ATR Stop-Loss & Position Size
Model ATR-based stops with an explicit unit value and risk budget.
- Drawdown & Recovery Calculator
See the loss amount and percentage gain needed to recover.
This tool is provided for general informational and workflow purposes only. It does not constitute financial, investment, tax, or professional advice. All calculations run in your browser; no input data is transmitted or stored.