Position Size Calculator
Calculate the exact lot size to trade for any of 21 forex and commodity instruments. Enter your account balance, the percent you're willing to risk on this trade, and your stop-loss — we'll size the position so a loss caps at your risk budget.
Enter your inputs to see results
Provide account balance, risk %, entry and stop-loss prices.
How to use the position size calculator
- Pick the instrument you're trading (EUR/USD, gold, oil, etc.) using the search box.
- Account balance — total funds in the account. The calculator assumes a USD account.
- Risk % — the percent you'll lose if the stop-loss is hit. 1% is the professional standard; 0.5% is conservative; 2% is aggressive.
- Entry & stop-loss prices — the calculator computes the distance in pips automatically.
- (Cross pairs only) enter the current exchange rate of the conversion pair (e.g. GBPUSD for EURGBP). Leave blank to use the default rate.
The formula
pips_at_risk = |entry − stop_loss| / pip_size
lots = risk_amount / (pips_at_risk × pip_value)
Pip value depends on the quote currency. For USD-quote instruments (EUR/USD, gold), it's a constant: $10/pip for forex majors, $1/pip for gold. For USD-base pairs (USD/JPY, USD/CAD) it varies with the current pair price. For cross pairs (EUR/GBP, EUR/JPY) it requires a separate conversion rate.
Frequently asked questions
What is a position size calculator?⌄
A position size calculator tells you how many lots (or units) to trade so that, if your stop-loss is hit, you only lose a fixed percentage of your account. It's the single most important risk-management tool in trading.
How is position size calculated?⌄
Position size = (Account balance × Risk %) ÷ (Stop-loss distance in pips × Pip value). The pip value depends on the instrument and, for cross pairs, on the current exchange rate of the conversion pair (e.g. USDJPY for JPY-quoted instruments).
What is a good risk % per trade?⌄
Most professional traders risk 0.5% – 2% per trade. The standard recommendation is 1%, which gives roughly 100 losing trades before a 63% drawdown — survivable for any reasonable strategy.
Is this calculator free?⌄
Yes. No sign-up, no email required, no usage limits. It uses the same math as the TradeVisor mobile app and is verified against 32 golden test values to ensure parity.
Does it work for cross pairs like EUR/GBP or EUR/JPY?⌄
Yes. Cross pairs require an additional conversion rate (e.g. GBP/USD for EUR/GBP) so the pip value can be expressed in USD. The calculator asks for this rate automatically and provides a sensible default.
Want AI-driven trade setups, not just sizing?
TradeVisor's AI scans 21 instruments multiple times a day and tells you which way to lean, with confidence scores and risk plans. Free to view predictions.
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