Lot size = the cash you are willing to lose ÷ (the stop distance in pips × the value of one pip per lot). On a $10,000 account risking 1% ($100) with a 50-pip stop on EUR/USD, where a pip is worth $10 a lot, that is 100 ÷ (50 × 10) = 0.20 lots. Pairs not quoted in dollars have a different pip value, which the calculator takes from live prices.
Stop distance: 50.0 pips. One pip is worth $10.00 per lot, as on every pair quoted in USD.
1 lot = 100,000 units.
A pip is 0.0001 on most pairs and 0.01 on yen pairs. One standard lot is 100,000 units of the first currency, so a pip on a pair quoted in US dollars is worth $10 a lot. On any other pair the pip is worth 10 units of the second currency, turned into dollars at its live rate. Gold trades 100 oz a lot, so a 0.01 move is $1 a lot; silver trades 5,000 oz, so it is $50. Index CFDs here are $1 a point a lot, and shares are simply risk ÷ the distance to the stop.
A $10,000 account risking 1%, so $100 a trade, in every row. Sizes round down, so a trade never risks more than the chosen percentage.
| Trade | Stop distance | Pip value per lot | Size |
|---|---|---|---|
| EUR/USD long | 50 pips | $10.00 | 0.20 lots |
| GBP/CAD long | 72 pips | $7.10 | 0.19 lots |
| USD/JPY short | 50 pips | $6.67 | 0.30 lots |
| Gold long | 4000 pips | $1.00 | 0.02 lots |
| A stock long | $10.00 a share | n/a | 10 shares |
The GBP/CAD row is the one most calculators get wrong. Its pip is 10 Canadian dollars a lot, and at a USD/CAD rate of 1.4081 that is $7.10, not $10, so the same $100 risk buys 0.19 lots rather than 0.13.
Check the contract size in your platform: some brokers trade indices at $10 a point or gold at 10 oz a lot, which changes the size by ten. Round down, never up. And if the size comes out below 0.01 lots, the stop is too wide for the risk: widen the risk only if your plan allows it, otherwise skip the trade.
The same maths sizes every call on the Trade Desk once a member saves their account. For what a risk percentage costs over a losing run, see the risk per trade calculator.
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Get this week’s setupsDivide the cash you will risk by the stop distance in pips times the pip value per lot. $100 at risk with a 50-pip stop on EUR/USD is 100 ÷ (50 × 10) = 0.20 lots.
Ten units of the second currency per standard lot, converted to your account currency. On GBP/CAD that is 10 Canadian dollars, about $7.10 with USD/CAD at 1.4081.
At 1% risk you have $10 a trade. With a 20-pip stop on EUR/USD that is 10 ÷ (20 × 10) = 0.05 lots; with a 50-pip stop it is 0.02 lots.
Down. Rounding up risks more than you planned on every trade, and over a losing run that difference compounds.
A standard lot is 100,000 units, a mini lot 10,000 (0.10) and a micro lot 1,000 (0.01). Most brokers let you trade in steps of 0.01 lots.