Forex Lot Size Calculator — Position Size for MT4 & MT5

Lot Size Calculator

Position size from account balance, risk % and stop-loss distance.

Account balance ($)

Risk per trade (%)

Stop-loss (pips)

Pip value per 1.0 lot ($)

Position size

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Pip value per 1.0 lot: $10 for most USD-quoted majors (EURUSD, GBPUSD). Use the pip calculator for other pairs.

What the lot size calculator does

Position sizing is the single biggest driver of whether an account survives. This forex lot size calculator converts a risk percentage into an exact lot size, so every trade risks the same fixed amount no matter the stop-loss distance.

The formula

Lot size = (Account balance × Risk %) ÷ (Stop-loss in pips × Pip value)

For USD-quoted majors the pip value per 1.00 lot is about $10. For other pairs, use our pip value calculator first.

How to size a trade in 3 steps

Enter your account balance and the percentage you are willing to risk (1–2% is standard).
Enter the stop-loss distance in pips for the trade.
The calculator returns the lot size that keeps your loss at exactly that risk if the stop is hit.

Frequently asked questions

What is a safe lot size in forex?

Most professional traders risk 1–2% of account equity per trade. The correct lot size is whatever keeps a stop-loss hit to that fixed percentage — which is exactly what this calculator returns.

Does this work for MT4 and MT5?

Yes. Lot size is broker- and platform-independent, so the result applies to MetaTrader 4, MetaTrader 5 and any other platform.

How is lot size calculated?

Lot size = (account balance × risk %) ÷ (stop-loss in pips × pip value per lot). Enter those inputs above and the calculator does the math instantly.

Want this enforced automatically on every trade?

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