how to calculate lot size for gold
Verdict
- Gold lot size = the amount you are prepared to lose ÷ (stop distance in US dollars × ounces per lot). With a 100-ounce lot, a $100 risk and a $5 stop give 0.2 lots. Pepperstone, our pick, shows the contract size in each platform's symbol specification.
- On a 100-ounce contract, every $1 move in gold is worth $100 per lot, $10 per 0.1 lot and $1 per 0.01 lot.
- Then check margin: at Pepperstone's 1:20 retail limit in Australia, margin is 5% of the position's value.
- Add costs last: 0.2 lots on Pepperstone Razor (cTrader, USD account) costs about $2.40 in average spread and $1.40 in commission per round trip.
Lot size is a risk decision, not a leverage decision. You fix the amount you're willing to lose, find where your stop belongs on the chart, and the lot size follows. Leverage only decides whether you have enough margin to open it.
The formula, using Pepperstone's contract details
Before you calculate, open XAU/USD's symbol specification in your platform (in MT5, right-click the symbol and choose Specification). It shows how many ounces one lot represents; 100 ounces is the usual standard gold lot. Then: lots = risk in dollars ÷ (stop distance in dollars × ounces per lot). Pepperstone quotes gold in US dollars per ounce on all its Australian platforms, from MT4 and MT5 to cTrader, TradingView and its own app, so the same arithmetic works everywhere.
Affiliate link — we may earn a commission at no extra cost to you.
Step by step
- Choose your risk per trade, for example 1% of your balance.
- Place the stop where your trade idea is proven wrong, and measure the distance from entry in dollars.
- Work out what $1 of movement is worth per lot: the number of ounces per lot.
- Divide your risk by (stop distance × ounces per lot).
- Round down to the platform's smallest lot step.
- Check that the margin fits comfortably in your free balance.
- Subtract the spread and commission from your expected gain.
Worked examples on a 100-ounce lot
The second and third rows show why a wider stop doesn't mean more risk: doubling the stop distance while doubling the risk leaves the size unchanged.
| Balance | Risk | Risk in $ | Stop distance | Lot size |
|---|---|---|---|---|
| $2,000 | 1% | $20 | $4 | 0.05 |
| $10,000 | 1% | $100 | $5 | 0.2 |
| $10,000 | 2% | $200 | $10 | 0.2 |
| $25,000 | 0.5% | $125 | $2.50 | 0.5 |
Then check the margin
Margin = lots × ounces per lot × gold price ÷ leverage. Pepperstone's retail limit on gold in Australia is 1:20. At an illustrative price of $3,000 an ounce (use the live quote), 0.2 lots is 20 ounces worth $60,000, which needs $3,000 of margin. On a $10,000 balance that ties up 30% of your funds for one trade, a sign to size down or wait if you hold other positions.
If your account is in AUD
Gold is priced in US dollars, so convert your risk first. With A$150 to risk and an illustrative rate of 0.65, that is US$97.50; divided by a $5 stop on 100 ounces, that gives 0.195, which rounds down to 0.19 lots. On Pepperstone Razor via MT5 an AUD account pays AUD 4.50 commission per side on gold; the Standard account has no commission and an average spread of 0.19.
Sources
Leverage, commission and spread figures as published by Pepperstone.
What is 0.01 lots of gold?
On a 100-ounce contract, one ounce, so a $1 move in gold changes the position's value by $1.
Does higher leverage let me trade a bigger lot safely?
No. Leverage lowers the margin required, but your loss at the stop depends only on lot size and stop distance.
Is a lot the same size on cTrader as on MT5?
The underlying amount is the same, but cTrader can display volume in ounces rather than lots, so 0.2 lots may appear as 20 oz.
Gold CFDs are complex and leveraged, and stops can fill beyond their level in fast markets, so actual losses can exceed what you planned. Prices and rates above are illustrative. Read the PDS and TMD; this is general education, not investment advice.