PipGauge

Home › Calculators › Position Size

Position Size Calculator

Decide how much you are willing to lose, and this works backwards to the lot size that keeps that risk fixed — rounded down to your broker's lot step.

Your risk

$10 for most USD-quoted pairs on a USD account. For cross pairs, get the exact figure from the Pip Value Calculator first.
Smallest lot increment your broker allows. We round down so you never exceed your risk.
lots = (balance × risk%) ÷ (stop-loss pips × pip value per lot)

Position to take

Lots (rounded to your step)—
Exact lots—
Units—
Amount at risk—
Lot tierSize
Trade-cost check

See what a real trade would cost you

Before you place this, compare brokers on the one number that matters — the all-in cost of spread and commission — using our open, for-sale-proof methodology.

Compare broker trading costs →

Disclosure. Some outbound links may be affiliate links; they never change a calculator’s result. How we make money.

Risk warning. CFDs are complex instruments and carry a high risk of losing money rapidly due to leverage. Between [XX]% of retail investor accounts lose money when trading CFDs with a given provider — a per-broker figure we publish only once verified (reviewed quarterly). Consider whether you understand how CFDs work and can afford the risk. Full risk disclosure.

Educational tools for non-US traders · not directed at US persons.

Quick answer

Position size in lots = (account balance × risk%) ÷ (stop-loss in pips × pip value per lot). On a $10,000 account risking 2% with a 50-pip stop and a $10 pip value, that is 200 ÷ 500 = 0.4 standard lots. Always round down to your broker's lot step so the actual risk never exceeds your plan.

How it works

What position sizing does

Position sizing flips the usual question around. Instead of guessing a lot size and seeing what happens, you fix the most you will lose on the trade and let the math return the size that produces exactly that risk. It is the single biggest lever a trader controls.

The formula

risk amount = account balance × (risk% / 100)

lots = risk amount ÷ (stop-loss in pips × pip value per lot)

The pip value per lot must already be in your account currency. For most USD-quoted pairs on a USD account that is $10 per standard lot; for cross pairs, get the exact figure from the Pip Value Calculator first.

How to use this calculator

  1. Enter your account balance and the percentage you are willing to risk on this trade.
  2. Enter the distance from entry to stop-loss, in pips.
  3. Enter the pip value per standard lot in your account currency.
  4. Set your broker's smallest lot step — the result is rounded down to it.

Worked example 1 — the 2% rule

A $10,000 account risking 2% can lose $200. With a 50-pip stop and a $10 pip value, the per-lot risk is 50 × 10 = $500, so 200 / 500 = 0.4 standard lots (40,000 units). If price hits the stop, the loss is the planned $200.

Worked example 2 — a smaller account

A $5,000 account risking 1.5% can lose $75. With a 25-pip stop and a $10 pip value, per-lot risk is $250, so 75 / 250 = 0.30 lots. Tightening the stop to 25 pips lets you trade a larger size for the same dollar risk.

When position sizing matters

It matters most when your stop distance changes from trade to trade. A fixed lot size means a tight-stop trade and a wide-stop trade carry very different dollar risk; sizing from risk keeps every loss the same size, which is what makes a strategy's expectancy meaningful.

Common mistakes

  • Rounding up. Rounding the lot size up pushes your real risk above plan. This tool always rounds down to your lot step.
  • Using the wrong pip value. On a cross-currency account the pip value is not $10 — compute it first, otherwise the size is wrong.
  • Ignoring spread and slippage. Your real loss is the stop distance plus spread and any slippage; size with a small buffer if your stop is tight.

Frequently asked questions

How do I calculate forex position size from risk percent?
Multiply your balance by your risk percent to get the dollar risk, then divide by the stop-loss in pips times the pip value per lot: (balance × risk%) ÷ (stop pips × pip value).
What lot size should I trade on a $10,000 account?
It depends on your risk and stop. Risking 2% with a 50-pip stop on a $10 pip value gives 0.4 standard lots. Change the stop or risk and the size changes — there is no single answer.
Why does the tool round the lot size down?
Rounding up would make your actual loss larger than the amount you planned to risk. Rounding down to your broker's lot step keeps the real risk at or below your limit.
How much should I risk per trade?
Many traders cap risk at 1-2% of the account per trade so a losing streak does not do lasting damage. This is a risk-management convention, not advice — choose a level you can sustain.
Do I use the same pip value for every pair?
No. The $10-per-lot figure only holds for USD-quoted pairs on a USD account. For yen pairs, cross pairs or a non-USD account, calculate the pip value first with the Pip Value Calculator.
Does position size account for leverage?
Position size is driven by your risk and stop, not leverage. Leverage only sets the margin needed to hold the position — check that with the Margin Calculator once you have the size.

Related calculators

Pip ValueMarginProfit / Loss