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Position Size Calculator
risk the right amount, every trade.

Position size (lots) = (account balance × risk %) ÷ (stop-loss in pips × pip value per lot). Example: a $10,000 account risking 1% with a 25-pip stop on EURUSD (pip value $10) = $100 ÷ (25 × $10) = 0.40 lots.

Most pros risk 0.5–2%. 1% is the standard.
Gold: 1 pip = $0.10 of price on most platforms.
0.40
Lots
40,000
Units
$100
Amount at risk

How the calculation works

The formula is lots = (balance × risk%) ÷ (stop pips × pip value). You decide the two inputs that are actually yours to control — how much of the account one trade may cost you, and where the trade is wrong (the stop). The lot size is then a calculation, not a feeling. Doubling your stop distance halves your size; it never has to mean doubling your risk.

JPY-pair pip values move with the USDJPY rate (≈ $6.70 per pip per lot at 150.00); the calculator uses that approximation. For exact per-broker values, check the contract specification in your platform.

Sizing is half the job. Tracking it is the other half.

Knowing your size is worthless if you don't know whether your 1%-risk trades actually perform better than the days you "felt confident" and doubled it. The free RB Trading journal logs risk % on every trade and shows you the win rate at each risk level — most traders find their oversized trades lose more often, not just bigger.

Track your next 50 trades free →
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By RB Trading · Updated 1 Aug 2026 · Free forever, no signup needed · Figures are estimates — confirm contract sizes with your broker.
FAQ

Frequently asked questions

How do I calculate position size in forex?

Position size (lots) = (account balance × risk %) ÷ (stop-loss in pips × pip value per lot). Example: a $10,000 account risking 1% with a 25-pip stop on EURUSD (pip value $10/lot) = $100 ÷ (25 × $10) = 0.40 lots.

What percentage of my account should I risk per trade?

Most professional and prop-firm traders risk 0.5%–2% per trade, with 1% the most common. At 1% risk it takes 10 consecutive losses to draw down roughly 10% — inside most prop firms' maximum drawdown limit.

What is the pip value for gold (XAUUSD)?

For XAUUSD, 1 standard lot is 100 oz, so a $0.10 price move (one pip on most platforms) is worth $10 per lot — the same per-pip value as EURUSD, but gold moves many more pips per day, so stops are wider and sizes smaller.