Position Size Calculator
Supported markets
This page works as a forex position size calculator, a stock position size calculator and a crypto position size calculator at the same time. One set of inputs covers every market, because the underlying question is always the same: how many units can I hold so that a stop-out costs me exactly what I decided to risk?
- Forex — majors, minors and crosses, quoted against USD, EUR, GBP, JPY and other currencies.
- Metals, energies and indices — XAU/USD, XAG/USD, WTI, Brent, natural gas and the main index CFDs.
- Stocks and ETFs — enter any ticker, its entry price and its stop price.
- Crypto futures — major USDT perpetuals (BTCUSDT, ETHUSDT, SOLUSDT and others).
- Anything else — pick Custom instrument and type your own contract size and unit step.
Contract specification defaults are editable. Brokers differ, so the Unit step and Contract size fields stay under your control rather than being guessed for you.
How position size is calculated
Every result on this page comes from four inputs: risk budget, stop distance, spread and commission.
- Risk budget = account balance × risk %, or the fixed amount you type in.
- Effective stop distance = |entry − stop price| + spread. The spread is what you actually lose at entry, so it belongs inside the stop distance, not next to it.
- Units = (risk budget − commission) ÷ (effective stop distance × quote→account rate). Commission is paid before it can be risked, so it is subtracted from the budget.
- Tradable size = units rounded down to your broker's unit step. Rounding never increases risk.
Position value = units × entry price × quote→account rate. Margin required = position value ÷ leverage. Exposure = position value ÷ account balance.
Rounding, spread and commission
Most calculators stop at the raw formula and print a number that no broker will accept. This one shows both numbers side by side: Size without costs is the raw formula result, and the main Position size is what you can actually place after the spread, the commission and your broker's minimum increment are applied.
Max loss incl. costs recomputes the worst case from the rounded size, so you can see that it still fits inside your risk budget instead of assuming it does.
Profit targets are optional. When you enter a take-profit price, the Risk : reward figure compares the distance to your target against the distance to your stop, including the spread.
FAQ
Is this a forex position size calculator?
Yes. Default is EUR/USD with a standard lot of 100,000 units. Pick any other pair from the instrument list or switch to Custom for a non-standard contract.
Can I use it as a stock position size calculator?
Switch to Stocks, enter the ticker price and stop price. Unit step defaults to one full share, which matches how share orders are placed.
Does it work as a crypto position size calculator?
Yes. Switch to Crypto, pick a USDT pair, and enter entry, stop and optional leverage. Leverage changes the margin you post, not the amount you risk.
Why is the result smaller than on other calculators?
Because the spread and the commission are inside the risk budget here. Other tools often ignore both and give you a size whose real loss exceeds what you planned.
Do I need an account to use it?
No. There is no sign-up, no login and nothing is uploaded. Every calculation runs in your browser.