Volatility and position sizing for gold

Gold often moves more in a day, in percentage terms, than major currency pairs. The same position-sizing method still works, but the inputs are different, and getting them wrong can multiply your risk. This lesson walks through the calculation step by step.

Dollars per point

On a contract of 100 troy ounces per lot, which is common but not universal:

• A 1.00 USD move in gold = 100 oz × 1.00 = 100 USD per lot.
• A 0.10 USD move = 10 USD per lot.
• A 0.01 USD move = 1 USD per lot.

If your provider uses a different contract size, every figure in this lesson changes in proportion. On a 10 oz contract, for example, a 1.00 USD move is worth 10 USD per lot. Check your platform's contract specification before trading.

The sizing formula for gold

The logic is the same as for currency pairs:

• Risk amount = account balance × risk %
• Loss per lot at the stop = stop distance in USD × ounces per lot
• Position size in lots = risk amount ÷ loss per lot at the stop

Worked example: 1% risk with a 10 USD stop

You have a 20,000 USD account and risk 1% per trade. Your analysis puts the stop 10.00 USD below your entry. The contract size is 100 oz per lot.

Step 1 – risk amount. 20,000 × 1% = 200 USD.

Step 2 – loss per lot at the stop. 10.00 USD × 100 oz = 1,000 USD per lot.

Step 3 – position size. 200 ÷ 1,000 = 0.20 lots, which is 20 troy ounces.

Check: 20 oz × 10.00 USD = 200 USD, exactly 1% of the account.

What about margin?

Using an example gold price of 2,000.00, the notional value is 0.20 × 100 oz × 2,000 = 40,000 USD. At 20:1 leverage the required margin is 40,000 ÷ 20 = 2,000 USD. That is the deposit to open the trade; your risk remains the 200 USD set by your stop. Notice that the position's notional value is twice your account balance, which is why the stop and the size matter so much.

A wider stop

If your analysis instead calls for a 25.00 USD stop:

• Loss per lot = 25.00 × 100 = 2,500 USD.
• Position size = 200 ÷ 2,500 = 0.08 lots, or 8 oz.
• Check: 8 oz × 25.00 USD = 200 USD.

The wider the stop, the smaller the position, and the money at risk stays the same.

Comparing volatility with EUR/USD

Average True Range (ATR) measures the average size of recent price bars, including gaps. Comparing ATR as a percentage of price shows how much each instrument typically moves.

The figures below are illustrative only; real values change constantly.

In this illustration, gold's typical daily range is more than twice as large as EUR/USD's in percentage terms. That has practical consequences:

• Stops need more room. A stop that is tight relative to gold's normal daily movement is likely to be hit by ordinary noise. In the example above, a 10.00 USD stop is only a third of the illustrative daily ATR, which may suit a short-term trade but would be tight for a trade held over several days.
• Positions are smaller. A wider stop at the same percentage risk means fewer ounces.
• Volatility changes. Gold's ATR can rise sharply around major news or periods of stress. Recalculate rather than reusing yesterday's size.

Using ATR to set the stop

Some traders base the stop on a multiple of ATR on their trading timeframe. For example, if the 1-hour ATR on gold is 6.00 USD, a stop of 1.5 × ATR is 9.00 USD. On a 20,000 USD account at 1% risk:

• Loss per lot = 9.00 × 100 = 900 USD.
• Position size = 200 ÷ 900 = 0.222 lots, rounded down to 0.22 lots.
• Check: 0.22 × 100 × 9.00 = 198 USD, just under the 200 USD limit.

Common mistakes

• Copying lot sizes from currency trading. 0.50 lots of EUR/USD and 0.50 lots of gold carry very different risk.
• Confusing "pips" and "points". Measure the stop in US dollars per ounce to avoid misreading your platform.
• Ignoring contract size. Always confirm how many ounces one lot represents with your provider.

Gold can gap and spike around news, so a stop may fill at a worse price than planned. Leverage magnifies both gains and losses.

Key takeaways

• On a 100 oz contract, a 1.00 USD move is worth 100 USD per lot; confirm your own contract size.
• Position size = risk amount ÷ (stop distance in USD × ounces per lot).
• 20,000 USD at 1% risk with a 10.00 USD stop gives 0.20 lots, or 20 oz.
• Gold's daily range is often much larger than EUR/USD's in percentage terms, so stops are wider and positions smaller.
• Recalculate size for every trade, and allow for gaps and spikes that can push losses past your stop.