Calculator · position size
Forex lot size calculator
Enter your balance, the share of it you will risk and your stop-loss in pips to get the position size in lots. Risking 1% of $5,000.00 with a 20-pip stop on EUR/USD gives 0.25 lots.
- 19 Oct 2026latest broker data check
Low Spread Brokers does not give personal investment advice.
Lot size and risk calculator
Majors, yen pairs and crosses on a USD, GBP, EUR or AUD account. Enter the balance in your account currency; the pip value is converted at the rate you give.
The prefilled exchange rate is a round example; replace it with the live quote. Spread and commission are not in the formula. Round the result down to your broker’s lot step, usually 0.01.
Result
Money at risk: $50.00 · One standard lot: $10.00 a pip
Lots = balance × risk % ÷ (stop in pips × pip value of one lot in the account currency)
$50.00 ÷ (20 × $10.00) = 0.25
Key takeaways
- 1Lots = money at risk ÷ (stop in pips × pip value per lot): $50.00 ÷ (20 × $10) = 0.25 lots.
- 2Set the stop from the chart first, then let the size follow: doubling the stop to 40 pips cuts the size to 0.125 lots for the same $50.00.
- 3On USD/JPY at 150 a pip is $6.67 per lot, so the same risk and stop allow 0.37 lots.
- 4Check the margin too: 0.25 lots of EUR/USD at 1.1000 ties up $916.67 at 1:30.
Retail leverage caps in the United Kingdom
Leverage does not enter the lot size formula; it decides whether you have the margin to open the size it gives. The most leverage a UK retail client can be given when opening a position. ESMA rules in the EU and ASIC rules in Australia set the same 1:30 on major pairs; Singapore’s MAS sets 1:20.
- FX majors1:30
- FX non-majors, gold, major indices1:20
- Commodities (ex gold), non-major indices1:10
- Individual equities1:5
- Cryptoassetsbanned (crypto derivatives may not be sold to retail clients)
Source: FCA PS19/18 and PS20/10, compiled in our country reference and not yet re-verified; see the sources on this page.
The lot size formula
Position size in lots = (account balance × risk %) ÷ (stop-loss in pips × pip value of one lot). The numerator is the most you accept to lose on the trade; the denominator is what one lot loses if the stop is hit.
With $5,000.00, 1% risk and a 20-pip stop: $50.00 ÷ (20 × $10) = 0.25 lots, or 25,000 units of EUR/USD.
| Risk per trade | Money at risk | Lots |
|---|---|---|
| 0.5% | $25.00 | 0.12 |
| 1% | $50.00 | 0.25 |
| 2% | $100.00 | 0.50 |
Pairs not quoted in US dollars
$10 a pip per lot holds only for pairs quoted in US dollars on a USD account. For USD/JPY the pip is ¥1,000 per lot, which at 150 is $6.67; the same $50.00 and 20-pip stop give $50.00 ÷ (20 × $6.67) = 0.37 lots.
On a GBP account the EUR/USD pip is $10 ÷ GBP/USD, £8.00 at 1.25. £5,000.00 with 1% risk and a 20-pip stop gives £50.00 ÷ (20 × £8.00) = 0.31 lots. Set the account currency and the rate in the calculator and it does this step for you.
Before you place the trade
Compare the size with your margin. 0.25 lots of EUR/USD at 1.1000 is $27,500.00 of exposure, $916.67 of margin at the 1:30 retail cap.
- Round down to the broker’s minimum step, usually 0.01 lot.
- A stop is not guaranteed: gaps and slippage can close the trade beyond it unless the broker offers a guaranteed stop, which usually costs extra.
- Spread and commission are not in the formula: a 1.0-pip spread on a 20-pip stop is 5% of the risk.
Brokers for small accounts
Why this order: brokers with a Tier 1 company whose published minimum deposit is USD 100 or less (or zero in any currency), ordered by our accounts score; ties broken by the overall score. Ranked from our data on 5 brokers, updated 19 Oct 2026.
- 1IC Markets8.1/10 · Minimum deposit $0 · 0.1 pipsVisit brokerUnpaid link
73.46% of retail investor accounts lose money when trading CFDs with this provider (IC Markets (EU) Ltd).
- 2ThinkMarkets7.6/10 · Minimum deposit $10 · Not measuredVisit brokerUnpaid link
75% of retail investor accounts lose money when trading CFDs with this provider (TF Global Markets (UK) Limited).
- 3Vantage8.0/10 · Minimum deposit $50 · 0.0 pipsVisit brokerUnpaid link
72.65% of retail investor accounts lose money when trading CFDs with this provider (Vantage Global Prime LLP).
Risk warning:
CFDs are complex instruments and come with a high risk of losing money rapidly due to leverage. Most retail investor accounts lose money. Consider whether you understand how CFDs work and whether you can afford the high risk of losing your money.
Low Spread Brokers does not give personal investment advice.
FAQ
Lot size and risk: questions
Short answers to the questions people ask about this calculation. The arithmetic is exact; exchange rates in the examples are round numbers, not market quotes.
Ask a questionWe cannot give personal investment advice.
1How do I calculate lot size in forex?
Divide the money you will risk by the stop-loss in pips times the pip value of one lot. $50.00 of risk and a 20-pip stop on EUR/USD (USD account, $10 a pip) give 0.25 lots.
Leverage caps: FCA, ESMA and ASIC rules as compiled in our country reference
2What lot size should I use with $100?
Risking 1% of $100 is $1. With a 20-pip stop on EUR/USD that is $1 ÷ (20 × $10) = 0.005 lots, below the usual 0.01 minimum, so even a micro lot risks 2% with that stop.
Leverage caps: FCA, ESMA and ASIC rules as compiled in our country reference
3How much should I risk per trade?
No regulator sets a figure. The arithmetic of a losing run is the argument: ten losses in a row cost 9.6% of the balance at 1% risk per trade and 40.1% at 5%. The table above shows the sizes at 0.5%, 1% and 2%.
Leverage caps: FCA, ESMA and ASIC rules as compiled in our country reference
4Does the calculator work for gold or indices?
No. Their contract sizes and point values differ by broker and instrument. Take the value of one point from your broker’s contract specification and divide the money at risk by the stop times that value.
Leverage caps: FCA, ESMA and ASIC rules as compiled in our country reference
5Why is the lot size different on USD/JPY?
Because the pip is counted in yen: ¥1,000 per lot, $6.67 at 150 on a USD account instead of $10. The default example then gives 0.37 lots, not 0.25. Pick USD/JPY in the calculator and enter the current rate.
Leverage caps: FCA, ESMA and ASIC rules as compiled in our country reference
Sources
The sizing arithmetic is standard; the sources cover the leverage caps used in the margin check.
- FCA PS19/18: restrictions on CFDs for retail clientsChecked on 20 Oct 2026
- ESMA: prohibition of binary options and restriction of CFDs for retail investorsChecked on 20 Oct 2026
- ASIC: search ASIC’s registersChecked on 20 Oct 2026