Imperial Research Position size calculator
Position size calculator: forex, gold and Nasdaq
Size every trade from the stop, not from a feeling. Enter your balance, how much you are willing to lose and the distance to your stop; the calculator gives the lot size.
Checked 3 November 2026
The formula
Lots = risk in money / (stop distance x value per unit per lot). Risk in money is the balance times the risk percent. The value per unit depends on the instrument: about $10 per pip per standard lot on USD-quoted forex pairs, $100 per $1 move per lot on gold with 100-ounce lots, and whatever your broker sets per point on index CFDs.
Worked examples
| Trade | Risk | Stop | Value per unit per lot | Size |
|---|---|---|---|---|
| EUR/USD long | $100 | 20 pips | $10 per pip | 0.50 lots |
| Gold short | $100 | $5.00 | $100 per $1 | 0.20 lots |
| Nasdaq long | $100 | 40 points | $1 per point | 2.50 lots |
For pairs where the dollar is not the quote currency (USD/JPY, EUR/GBP), the pip value changes with the exchange rate; use your platform's pip value for those.
Questions
How do I calculate position size?
Risk in money divided by the stop distance times the value of one unit of movement for one lot. With $10,000, 1% risk ($100) and a 20-pip stop on EUR/USD ($10 per pip per lot), the size is 100 / (20 x 10) = 0.5 lots.
What lot size for gold (XAUUSD)?
One standard lot of gold is usually 100 ounces, so a $1 move is worth $100 per lot. With $100 of risk and a $5 stop, the size is 100 / (5 x 100) = 0.2 lots. Check your broker's contract size.
How much should I risk per trade?
Many traders risk 0.5% to 1% of the account per trade. Inside a prop challenge with a 5% daily limit, 0.5% leaves room for several losers in a row.
Why is the Nasdaq value per point editable?
Brokers set the contract size of index CFDs differently: one lot can be worth $1, $10 or $20 per point. Look up the contract specification and enter it.