Forex Position Size & Lot Size Calculator
Size every trade by risk, not by guesswork.
Assumes ~$10 pip value per standard lot (typical USD-quoted forex pair). Adjust the pip value for other instruments.
A position size calculator tells you exactly how many lots to trade so a losing trade only costs the percentage of your account you decided to risk. Enter your balance, the percentage you are willing to risk, and your stop-loss in pips — the calculator returns your risk amount and the correct position size in lots. Consistent position sizing is the single biggest difference between traders who survive and traders who blow accounts.
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Automate your risk rules in an EAFrequently Asked Questions
How do you calculate position size?
Position size (lots) = (account balance x risk percent) divided by (stop-loss in pips x pip value per lot). For most USD-quoted forex pairs the pip value is about $10 per standard lot, so risking 1 percent of a $10,000 account with a 50-pip stop gives 0.2 lots.
What percentage should I risk per trade?
Most professional traders risk 0.5 to 2 percent of account equity per trade. Risking more than 2 percent makes a normal losing streak account-threatening.
Does this work for crypto and indices?
Yes — set the pip/point value per lot for your instrument and the maths is the same. The default $10 assumes a standard forex lot on a USD-quoted pair.