Free tool
XAUUSD lot size calculator
Size a gold position from your risk and a stop measured in dollars. The gold contract size is already filled in, and every step of the arithmetic is shown.
- Money at risk
- $100.00
- Loss per 1.00 lot
- $500.00
- Units
- 20
- Exact (unrounded)
- 0.2000 lots
Rounded down to 0.01 lots — rounding up would risk more than the 1% you asked for. Excludes spread, commission and swap.
Why gold sizing trips people up
Most gold sizing mistakes come from unit confusion. Traders think about gold in whole dollars — “my stop is five dollars” — but pip-based calculators expect a pip, and for XAUUSD a pip is usually $0.10. Enter 5 where the tool wanted 50 and the position comes out ten times too small; enter it the other way and it is ten times too large.
This calculator sidesteps that by letting you enter the stop in whichever unit you actually think in, and converting it for you.
The formula, with gold's contract size
One standard lot of XAUUSD is 100 troy ounces. So a $1 move in the gold price is $100 per standard lot — which is all the calculation needs.
risk amount = balance × risk % loss per lot = stop distance in $ × 100 oz position = risk amount ÷ loss per lot
A worked example
A $20,000 account, risking 1%, with a stop $5.00 away from entry:
risk amount = 20,000 × 1% = $200 loss per lot = 5.00 × 100 = $500 position = 200 ÷ 500 = 0.40 lots
Gold moving $5 against 0.40 lots costs $200 — the 1% that was budgeted. If the same account used a $10 stop, the position would halve to 0.20 lots and the risk would stay $200.
Assumptions
100 ounces per standard lot is the common retail gold contract, but it is a convention rather than a law — some brokers differ, especially on cent and micro accounts. Check yours. The result assumes a USD-denominated account, since XAUUSD is quoted in USD; on a non-USD account the figure is in dollars and needs converting.
Spread, commission and swap are excluded, and gold spreads widen around news and the session roll. Sizes are rounded down to 0.01 lots so the position never exceeds the risk you asked for.
Gold is volatile, and sizing is where that is handled
Gold routinely moves more in a session than a major FX pair does in a week. That is not an argument for trading it smaller as a rule — it is an argument for the stop distance, and therefore the position size, being decided before the trade rather than during it.
Frequently asked questions
- What is one standard lot of XAUUSD?
- 100 troy ounces, which is the common retail gold contract and the figure this calculator uses. A $1 move in the gold price is therefore $100 per standard lot. Brokers differ, particularly on mini and micro accounts, so confirm yours before sizing a live position.
- How many dollars is a pip on gold?
- A XAUUSD pip is usually $0.10, so a $5 stop is 50 pips. This is where most gold sizing errors come from: entering 5 where a pip-based tool expected 50 undersizes the position by a factor of ten. This calculator accepts the stop in dollars or in pips and converts for you.
- How do I calculate gold lot size from a dollar risk?
- Divide the money you are risking by the stop distance in dollars multiplied by 100 ounces. Risking $200 with a $5 stop gives $200 ÷ ($5 × 100) = 0.40 lots.
- Why is my gold position smaller than I expected?
- Gold moves in whole dollars far more readily than a forex pair moves in whole pips, so a stop that feels tight in gold terms is a large price distance. At a fixed cash risk a wider stop must produce a smaller position — that is the sizing working, not failing.
- Does this work for XAGUSD and other metals?
- Use the general position size calculator for silver, oil, indices and forex pairs. It is the same arithmetic with the contract size of the instrument you choose rather than gold’s 100 ounces.