Position Size Calculator

Position sizing determines how much capital you commit to a single trade — and it's one of the most important risk management decisions you'll make before every position. This calculator does the math for you: enter your account balance, how much you're willing to risk, and your stop loss distance, and it tells you exactly how large a position keeps your risk consistent.

Don't know your pip value? Calculate it here
Amount at risk100.00
Position size (lots)0.20 lots

Risking 100.00 with a 50-pip stop loss means a position size of 0.20 lots.

Check the margin this position requires

This content is for educational purposes only and does not constitute financial advice. This tool provides estimates and should not be your sole basis for trading decisions.

How This Calculator Works

Risk amount = Account balance × Risk percentage

Position size = Risk amount ÷ Stop loss distance

By fixing the percentage of your account you're willing to risk (commonly 1–2%, as covered in our risk management guide) and your stop loss distance, the calculator works backward to tell you the position size that keeps those two numbers consistent — rather than picking a position size first and hoping the risk works out.

What You'll Need to Enter

  • Account balance: your total trading capital in your account currency
  • Risk percentage: how much of your account you're willing to risk on this specific trade
  • Stop loss distance: how far your stop loss is from your entry price, in pips (forex) or price units (stocks, commodities, indices)
  • Pip value (forex only): the value of one pip for your position size — use our pip value calculator first if you don't know this

Why Position Sizing Matters More Than It Seems

Two traders can take the exact same trade — same entry, same stop loss, same take profit — and have completely different outcomes simply because they used different position sizes. A position that's too large relative to your account can turn a normal, expected loss into a serious setback; one that's too small means your risk management is overly conservative and your capital isn't working efficiently. Calculating position size consistently, every time, removes the guesswork.

Frequently Asked Questions

What risk percentage should I use?

There's no single correct number, but 1–2% per trade is a commonly cited starting point that limits the impact of any single loss or losing streak — see our risk management guide for the reasoning.

Does this calculator account for leverage?

Position size and leverage are related but different: this calculator tells you how large a position to open based on risk; our margin calculator then tells you how much margin that position requires given your leverage.

What if I don't know the pip value for my currency pair?

Use our pip value calculator first — it calculates pip value based on the currency pair, trade size, and your account currency.