acalculator

What lot size should I trade?

Type your account balance, the percent you accept to lose on one trade, and your stop loss in pips. Say how the pair relates to your account currency and type the rate. The lot size calculator gives the position in standard, mini and micro lots.

Your numbers

Pip size
Your account currency is
Standard lots
0.2

Risking 100 with a 50-pip stop, trade 0.2 standard lots (20,000 units).

Units
20,000
Mini lots
2
Micro lots
20
Money at risk
100
Pip value per standard lot
10
Lots rounded down to 0.01
0.2
Money at risk at the rounded size
100

Standard lots: 0.2. Risking 100 with a 50-pip stop, trade 0.2 standard lots (20,000 units).

The results are estimates for information only. They are not financial, tax, or legal advice. Check the numbers with your lender or a qualified professional before you decide. Terms of use

How to calculate

Works out the forex lot size (position size) that risks a chosen percent of your account if the stop loss is hit, in standard, mini and micro lots and units, from rates you type.

Example with the default inputs (Account balance 10,000, Risk per trade 1%, Stop loss (pips) 50, Pip size 0.0001 (most pairs), Your account currency is The quote currency (EUR/USD, USD account)): Risking 100 with a 50-pip stop, trade 0.2 standard lots (20,000 units).

Method: risk = balance × risk %; pip value per lot = 100,000 × pip size × (1, 1 ÷ price, or the quote-currency rate); lots = risk ÷ (stop pips × pip value per lot).

  • A standard lot is 100,000 units of the base currency; a mini lot 10,000; a micro lot 1,000.
  • The pair price and the conversion rate are typed by you; the page fetches no quotes.
  • Spread, commission, swap and slippage are not counted; a gap past the stop loses more.
  • Arithmetic is exact on the typed decimals; the rounded size is cut down, never up, to 0.01 lot.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Account balance 10,000, Risk per trade 1%, Stop loss (pips) 50, Pip size 0.0001 (most pairs), Your account currency is The quote currency (EUR/USD, USD account) gives Money at risk 100, Pip value per standard lot 10, Standard lots 0.2, Units 20,000, Mini lots 2, Micro lots 20, Lots rounded down to 0.01 0.2.Source: Commodity Futures Trading Commission, CFTC Glossary ("Pip": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm
  2. Account balance 5,000, Risk per trade 2%, Stop loss (pips) 30, Pip size 0.01 (yen pairs), Your account currency is The base currency (USD/JPY, USD account), Pair price 150 gives Money at risk 100, Pip value per standard lot 6.666667, Standard lots 0.5, Units 50,000.Source: Commodity Futures Trading Commission, CFTC Glossary ("Pip": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm
  3. Account balance 20,000, Risk per trade 1.5%, Stop loss (pips) 40, Pip size 0.0001 (most pairs), Your account currency is Neither (EUR/GBP, USD account), Quote currency in account currency 1.25 gives Money at risk 300, Pip value per standard lot 12.5, Standard lots 0.6.Source: Commodity Futures Trading Commission, CFTC Glossary ("Pip": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm
  4. Account balance 2,500, Risk per trade 1%, Stop loss (pips) 35, Pip size 0.0001 (most pairs), Your account currency is The quote currency (EUR/USD, USD account) gives Standard lots 0.071429, Lots rounded down to 0.01 0.07, Money at risk at the rounded size 24.5.Source: Commodity Futures Trading Commission, CFTC Glossary ("Pip": the smallest price unit of a commodity or currency). https://www.cftc.gov/LearnandProtect/AdvisoriesAndArticles/CFTCGlossary/index.htm

How it works

The arithmetic of a forex position, written out:

  • Money at risk R = balance × risk % ÷ 100.
  • Value of one quote-currency unit in the account currency c: 1 when the account currency is the quote currency (EUR/USD, USD account); 1 ÷ price when it is the base currency (USD/JPY at 150, USD account); the typed rate when it is neither (EUR/GBP, USD account, 1.25 USD per GBP).
  • Pip value per standard lot = 100,000 × pip size × c, with pip size 0.0001, or 0.01 for yen pairs.
  • Standard lots = R ÷ (stop loss in pips × pip value per standard lot).
  • Units = lots × 100,000. Mini lots = lots × 10. Micro lots = lots × 100.
  • Lots rounded down to 0.01 = ⌊lots × 100⌋ ÷ 100. Money at risk at the rounded size = rounded lots × stop loss × pip value per lot.

Every number is read exactly as typed (0.0001 is one ten-thousandth), so the rounding down is exact; each result is rounded once to a double-precision number.

Rules

  • Balance from 1 to 10¹². Risk more than 0% and at most 100%. Stop loss from 0.1 to 100,000 pips. Price and conversion rate from 0.000001 to 1,000,000.
  • The price is used only when the account currency is the base currency, and the conversion rate only when it is neither.

Output format. Standard lots show 4 decimals, mini lots 3, micro lots 2, units 0; money at risk and the rounded size show 2 decimals, and the pip value 4. Amounts are in the account currency.

Worked examples by hand

EUR/USD, USD account. R = 10,000 × 1% = 100. Pip value 100,000 × 0.0001 × 1 = 10. Lots = 100 ÷ (50 × 10) = 0.2, which is 20,000 units, 2 mini lots or 20 micro lots.

USD/JPY at 150, USD account. R = 5,000 × 2% = 100. Pip value 100,000 × 0.01 ÷ 150 = 6.6667. Lots = 100 ÷ (30 × 6.6667) = 0.5 (50,000 units).

EUR/GBP, USD account, GBP at 1.25. R = 20,000 × 1.5% = 300. Pip value 100,000 × 0.0001 × 1.25 = 12.5. Lots = 300 ÷ (40 × 12.5) = 0.6.

Rounding down. R = 2,500 × 1% = 25, stop 35 pips on EUR/USD: 25 ÷ 350 = 0.0714 lots. Rounded down to 0.07 lots, which risks 0.07 × 35 × 10 = 24.50.

Other questions people ask

How do I calculate lot size in forex?

Work out the money at risk (balance × risk %), then divide it by the stop loss in pips times the pip value of one standard lot. With $10,000, 1% risk and a 50-pip stop on EUR/USD: $100 ÷ (50 × $10) = 0.2 lots, or 20,000 units.

What is a pip worth?

For one standard lot (100,000 units), a pip is worth 100,000 × the pip size in the quote currency. On EUR/USD that is 100,000 × 0.0001 = $10. On USD/JPY at 150 it is 100,000 × 0.01 ÷ 150 = $6.67 for a USD account.

What if my account currency is in neither side of the pair?

Convert the pip value from the quote currency to your account currency. For EUR/GBP with a USD account and GBP worth $1.25, one pip on a standard lot is £10 × 1.25 = $12.50.

What are standard, mini and micro lots?

A standard lot is 100,000 units of the base currency, a mini lot 10,000, and a micro lot 1,000. 0.2 standard lots is 2 mini lots or 20 micro lots.

Why round the lot size down?

Most platforms accept sizes in steps of 0.01 lot. Rounding down keeps the loss at the stop at or below your risk limit; 0.0714 lots becomes 0.07 and risks $24.50 instead of $25.

Does this page use live exchange rates?

No. You type the pair price or the conversion rate, so the answer matches the rate you trade at. The page sends nothing and fetches no quotes.