To size a forex position, divide the amount you are willing to lose by the stop loss in pips multiplied by the pip value per lot. With a €5,000 account, 1% risk, a 25-pip stop and a pip value of 10, the position is 0.2 standard lots, or 20,000 units. A 1:2 target would make €100.
How do you calculate forex lot size?
Position sizing starts with the amount you will risk, not with the trade. Risk amount = balance × risk%. Lot size = risk amount ÷ (stop loss in pips × pip value per lot). A standard lot is 100,000 units of the base currency, a mini lot is 10,000 and a micro lot is 1,000. On a €5,000 account risking 1% (€50) with a 25-pip stop and €10 per pip per lot, the lot size is 50 ÷ (25 × 10) = 0.2 lots. The tool shows that in standard, mini and micro lots so you can type it into most platforms.
What is a pip and what is it worth?
For most pairs a pip is 0.0001 of the quote, and for yen pairs 0.01. The value of a pip depends on the pair and your account currency. For EUR/USD on a USD account, one pip on a standard lot is $10. On a EUR account it is about €9 to €10 depending on the rate. Your broker’s contract specification lists the exact value, and you can paste it into the pip value field.
Leverage and margin
Margin is the deposit your broker holds to keep the position open: units × price ÷ leverage. In the EU, retail leverage on major currency pairs is limited to 30:1, which means a 3.33% margin. The calculator reports the margin as a share of your balance, so you can see whether a trade uses too much of it. High margin use leaves little room before a margin call.
Risk rules that actually matter
- Risk 0.5% to 2% of your balance per trade. A series of ten losses at 2% costs about 18%, but at 10% it ruins the account.
- Decide the stop first, then size the position. Changing the stop to fit the size defeats the point.
- Include spread and slippage in your pip count, especially on news.
Converting profits and taxes in the Netherlands
Dutch private traders do not pay tax on actual forex gains. Instead your capital counts toward box 3, see the box 3 calculator. Professional trading can be taxed as business income. For currency conversion of withdrawals, use the USD to euro calculator, and to model the growth of an account with regular deposits, use the compound interest calculator.
How to use this calculator
- Enter your account balance and the percentage you risk per trade.
- Add the stop loss distance in pips and the pip value per standard lot.
- Set your broker’s leverage, the pair’s price and your target ratio.
- Read the lot size, units, margin and target profit.
Key figures at a glance
| Standard lot | 100,000 units |
|---|---|
| Mini / micro lot | 10,000 / 1,000 units |
| EU retail leverage (majors) | 30:1 |
| Formula | Lots = risk ÷ (stop pips × pip value) |
Frequently asked questions
Enough that a stop-loss hit costs the percentage you chose, commonly 0.5% to 2% of the account. The calculator shows the exact figure.
About $10 per standard lot on USD-quoted pairs for a USD account. Check your broker’s specification.
You can open a position worth 30 times your margin. At 30:1, a €1,000 deposit controls up to €30,000.
For private investors there is no tax on realised gains, but the capital counts in box 3 on 1 January.
Yes. Most retail traders lose money, and leverage amplifies losses. Never trade money you cannot afford to lose.