Lot Size Calculator — Forex Position Size in Lots

The Lot Size Calculator helps you determine the right position size for any forex trade in seconds. Enter your account balance, the percentage of your account you are willing to risk on this trade (e.g. 1–2%), the stop loss distance in pips, and the pip value per standard lot for the currency pair you are trading (default $10 for most USD-quoted pairs like EUR/USD).

Click "Calculate Lot Size" to see the recommended position in standard lots, mini lots, and micro lots. The tool also shows your exact dollar risk amount and maximum loss at the stop, so you can confirm it matches your intended risk before placing the trade.

Use a pip value other than $10 when trading cross pairs where neither currency is USD (e.g. EUR/GBP). Your broker's trading platform or a pip value calculator can supply the exact figure for any pair.

The lot size calculation follows three steps:

1. Risk Amount: Risk $ = Account Balance × (Risk % ÷ 100)
   Example: $10,000 × (2 ÷ 100) = $200
2. Standard Lots: Lots = Risk $ ÷ (Stop Loss Pips × Pip Value per Lot)
   Example: $200 ÷ (50 × $10) = 0.40 lots
3. Conversions:
   • Mini Lots = Standard Lots × 10
   • Micro Lots = Standard Lots × 100
   • Pip Value = Standard Lots × Pip Value per Lot

The default pip value of $10 per standard lot applies to all major USD-quoted pairs (EUR/USD, GBP/USD, AUD/USD). For USD-base pairs like USD/JPY or USD/CHF the pip value varies with the exchange rate and will differ. Always verify the pip value from your broker platform for precision.

Example 1 — Standard 2% Risk on EUR/USD

A trader has a $10,000 account, uses 2% risk per trade, and places a stop loss 50 pips away on EUR/USD (pip value: $10/lot).

• Risk amount: $10,000 × 2% = $200
• Lot size: $200 ÷ (50 × $10) = 0.40 standard lots
• Mini lots: 0.40 × 10 = 4.0 mini lots
• Micro lots: 0.40 × 100 = 40 micro lots
• Pip value at 0.40 lots: 0.40 × $10 = $4.00 per pip

If the stop is hit, the trader loses exactly $200 (50 pips × $4/pip = $200), which equals 2% of the account. Position sizing is working correctly.

Example 2 — Conservative 1% Risk with Tight Stop

A swing trader with a $5,000 account risks 1% per trade with a 20-pip stop loss on GBP/USD (pip value: $10/lot).

• Risk amount: $5,000 × 1% = $50
• Lot size: $50 ÷ (20 × $10) = 0.25 standard lots
• Mini lots: 2.5 | Micro lots: 25
• Pip value: 0.25 × $10 = $2.50 per pip

With only $2.50 per pip, account drawdown is minimal even during losing streaks. A run of 10 consecutive losses at 1% risk per trade reduces the account by approximately 9.6% — a recoverable setback for a disciplined trader.