Forex Lot Size Calculator

Example: calculating forex lot size

Assume your account balance is $10,000 and you want to risk 1% on one trade. That gives you a risk amount of $100.

If your stop loss is 25 pips and the pip value is $10 per pip for 1 standard lot, the correct position size is 0.40 lots.

That means a 25 pip loss would equal roughly $100 before spreads, commissions, swaps and slippage.

How the calculation works

This calculator turns your trade risk into a forex lot size.

Risk amount = account balance × risk %

Lot size = risk amount / (stop loss in pips × pip value per 1.00 lot)

Position units = lot size × contract size

If you do not know the pip value for your pair, calculate it first with the Pip Value Calculator.

How to use this in trade planning

Lot size should come from risk, not from guessing. Decide how much you are willing to lose, define the stop loss distance, then calculate the position size.

This keeps the trade risk consistent even when the stop loss changes from setup to setup.

This is where a trading journal matters. The calculator gives you planned size. The journal shows whether your real trades respected your risk rule.

Common questions

What is forex lot size?

Forex lot size is the position size of a forex trade. A common standard lot is 100,000 units, a mini lot is often 10,000 units and a micro lot is often 1,000 units.

What pip value should I enter?

Enter the pip value for 1.00 lot in your account currency. If you are unsure, use the Pip Value Calculator first or check your broker's instrument specification.

Should I include commissions and spread?

This calculator focuses on stop-loss risk. In real trading, spread, commissions, swaps and slippage can affect the final result.

Is this trading advice?

No. This is an educational risk-planning calculator. It does not tell you what to trade, when to trade, or what risk level is right for you.

Related trading tools

Continue the risk review with these free browser-based tools:

Pip Value Calculator
Position Size Calculator
Risk Reward Calculator
R-Multiple Calculator
Expectancy Calculator
Drawdown Recovery Calculator
Daily Loss Limit Calculator

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You can link directly to this free calculator from a trading website, blog, education page, or community resource page.

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https://forgalis.com/tools/forex-lot-size-calculator/

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