How it works
Most brokers quote gold as XAUUSD with a contract size of 100 troy ounces per 1.00 lot. That means a 1.00 USD move in the gold price changes a 1.00 lot position by 100 USD, and a 0.01 lot position by 1 USD.
- Money at risk = balance × risk %. With 1,000 USD and 1% risk you accept losing 10 USD if the stop-loss is hit.
- Loss per 1.00 lot = stop-loss distance × contract size. A 10 USD stop on 100 oz = 1,000 USD per lot.
- Lot size = money at risk ÷ loss per lot, rounded down to your broker's lot step: 10 ÷ 1,000 = 0.01 lot.
Tips
- Check the contract size in your platform: in MetaTrader 5, right-click XAUUSD in Market Watch → Specification. Some brokers use 10 or 1 oz.
- If the result is below your broker's minimum lot, even the smallest position would risk more than you chose. Use a tighter stop-loss only if your setup allows it, otherwise skip the trade.
- Spread and slippage add to the real loss, especially around news. Keep a buffer.
- Most professional traders risk 0.5–2% per trade. See our lesson on risk and position size.
Want this done automatically? All GoldLab gold EAs size every trade from a risk % and a fixed stop-loss.
For education only, not investment advice. Trading gold and CFDs is high risk and you can lose your capital.