Gold is the market where most new traders lose their first account, and it is rarely because they picked the wrong direction. It is because a "normal" lot size on a currency pair is a very large position on gold. A move that costs a few dollars on EURUSD can cost hundreds on XAUUSD.
The fix is not a feeling or a rule of thumb like "0.01 per $100". It is a short calculation you do before every trade: decide what you are willing to lose, measure the distance to your stop, and let the maths pick the size.
The three numbers you need
- Amount at risk. Your balance multiplied by the percentage you accept losing if the stop is hit. With $5,000 and 1%, that is $50.
- Stop distance in dollars of price. The gap between your entry and your stop loss, written as a price difference. Entry 4,050.00 and stop 4,044.50 is a distance of 5.50.
- Contract size. How many ounces one lot represents at your broker. On most MetaTrader 5 brokers it is 100 ounces.
The formula
First, work out what one full lot would lose at the stop:
Loss per lot = contract size × stop distance
Then divide the amount you are willing to lose by that figure:
Lot size = amount at risk ÷ loss per lot
Finally, round the result down to your broker's volume step, usually 0.01. Rounding up would risk more than you planned. Rounding down risks slightly less, which is the safe side.
Worked examples
| Balance | Risk | Stop distance | Loss per lot | Lot size |
|---|---|---|---|---|
| $1,000 | 1% = $10 | $5.00 | 100 × 5 = $500 | 0.02 |
| $5,000 | 1% = $50 | $8.00 | 100 × 8 = $800 | 0.06 (0.0625 rounded down) |
| $10,000 | 0.5% = $50 | $12.50 | 100 × 12.5 = $1,250 | 0.04 |
| $25,000 | 1% = $250 | $20.00 | 100 × 20 = $2,000 | 0.12 (0.125 rounded down) |
A handy shortcut falls out of the contract size: with 100 ounces per lot, every $1.00 the price moves is worth $1 per 0.01 lot. So 0.05 lots with a $6.00 stop loses about $30 at the stop. You can sanity-check any trade in your head this way.
If you would rather not do the arithmetic, the free lot size calculator does exactly these steps for gold, silver, indices, Bitcoin and the major forex pairs.
Pips, points and dollars: why gold confuses everyone
On currency pairs a pip has a fixed meaning. On gold it does not. Depending on who you ask, a gold "pip" is $0.01, $0.10 or $1.00, and MetaTrader shows distances in points, which on a two-decimal gold symbol are $0.01 each. A "50 pip stop" can therefore mean $0.50, $5.00 or $50.00, a factor of a hundred.
The simplest way out is to stop using pips for gold altogether. Measure the stop as a price difference in dollars (5.00, 12.50, 20.00) and size from that. If your platform shows points, divide by 100 on a two-decimal symbol: 550 points is a distance of 5.50.
Check your broker's contract size in MT5
Most brokers use 100 ounces per lot, but not all, and some offer mini or micro gold symbols with a different size. Checking takes ten seconds:
- Open the Market Watch window (Ctrl+M).
- Right-click XAUUSD (or your broker's gold symbol) and choose Specification.
- Read Contract size, Minimal volume and Volume step.
If the contract size is not 100, put your broker's figure into the formula. Everything else stays the same.
The small-account problem
Brokers set a minimum trade size, usually 0.01 lots. On gold that minimum is still worth $1 per $1.00 of movement, so it puts a floor under your risk:
- A $5.00 stop at 0.01 lots risks $5. On a $500 account that is already 1%.
- A $15.00 stop at 0.01 lots risks $15. On a $500 account that is 3%, whatever percentage you typed in.
When the formula gives a number below 0.01, you have three honest choices: use a tighter stop (only if the strategy still makes sense with it), accept a higher percentage risk knowingly, or skip the trade. What you should not do is round up to 0.01 without noticing that the real risk just doubled or tripled.
What the formula does not include
The formula measures the loss between your entry and your stop price. Three costs come on top:
- Spread. Gold spreads vary a lot between brokers and widen around news and the daily rollover. A 30-cent spread on a $3.00 stop is a 10% extra cost on every trade.
- Commission. Raw-spread accounts charge a fee per lot, usually per side.
- Slippage. In a fast market a stop can fill a little beyond its price.
On tight stops these costs are a large share of the risk, so round down and, if needed, lower the percentage slightly.
Five mistakes that blow gold accounts
- Copying a forex lot size. 0.10 lots on EURUSD with a 20-pip stop loses about $20. 0.10 lots on gold with a $20.00 stop loses $200.
- Sizing first, placing the stop second. The stop goes where the trade idea is wrong; the lot size follows from it, never the other way round.
- Mixing up pips and points. Always convert to a dollar distance before you calculate.
- Moving the stop further away after entry. That silently increases the risk the lot size was built for.
- Adding positions without recalculating. Two trades at 1% each in the same direction on the same symbol is a 2% bet on one idea.
Let the EA do it for you
If you trade gold with an Expert Advisor, the sizing should be automatic. Golden Box Breakout, for example, sizes every position from a risk percentage of your balance (or a fixed amount, or a fixed lot), places a hard stop on every trade, and checks volume limits and free margin before it sends an order. The calculation is the same one shown above; the robot just never skips it.