Forex Lot Size Calculator
Calculate exactly how many lots to trade based on your account size, risk tolerance, and stop loss distance. Never over-leverage a forex position again.
Most traders risk 1–2% per trade
$10 for EUR/USD, GBP/USD, and most USD-quoted pairs
Enter your account size, risk percentage, and stop loss distance, then click Calculate lot size to see exactly how many lots to trade.
For educational purposes only. Not financial advice. Read full disclaimer
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Lot Size Formula
Dollar Risk = Account Size × (Risk % ÷ 100)
Lot Size = Dollar Risk ÷ (Stop Loss Pips × Pip Value)
Mini Lots = Lot Size × 10
Micro Lots = Lot Size × 100
Units = Lot Size × 100,000
Pip value defaults to $10 for USD-quoted pairs (EUR/USD, GBP/USD, AUD/USD, NZD/USD).
Worked Examples
Example 1: $10,000 account, 2% risk, 50-pip stop on EUR/USD
You have a $10,000 account and want to risk 2% per trade. You're trading EUR/USD with a 50-pip stop loss. The pip value is $10 per standard lot.
- Dollar Risk = $10,000 × 2% = $200
- Lot Size = $200 ÷ (50 × $10) = $200 ÷ $500 = 0.40 standard lots
- Mini lots = 0.40 × 10 = 4.0 mini lots
- Units = 0.40 × 100,000 = 40,000 units
Example 2: $5,000 account, 1% risk, 25-pip stop on GBP/USD
You have a $5,000 account risking 1%. You're trading GBP/USD with a tight 25-pip stop. Pip value is $10 per standard lot.
- Dollar Risk = $5,000 × 1% = $50
- Lot Size = $50 ÷ (25 × $10) = $50 ÷ $250 = 0.20 standard lots
- Mini lots = 0.20 × 10 = 2.0 mini lots
- Units = 0.20 × 100,000 = 20,000 units
How to Use This Calculator
- Enter your account size — the total capital available in your trading account.
- Set your risk percentage — the percentage of your account you're willing to risk on this single trade. Most professionals use 1–2%.
- Enter your stop loss in pips — the distance from your entry to your stop loss level, measured in pips.
- Confirm pip value — the default $10 is correct for most USD-quoted pairs (EUR/USD, GBP/USD, AUD/USD). For JPY pairs or other crosses, use the Forex Pip Calculator to find the exact pip value.
- Click Calculate — the result shows your lot size in standard lots, mini lots, micro lots, and raw units alongside your exact dollar risk.
Frequently Asked Questions
- What is a standard lot in forex?
- A standard lot is 100,000 units of the base currency. On EUR/USD, one standard lot means you control €100,000. Mini lots are 10,000 units and micro lots are 1,000 units. Choosing the right lot size is the primary lever for controlling your risk.
- Why is pip value $10 for most pairs?
- For USD-quoted pairs (where USD is the quote currency, like EUR/USD or GBP/USD), a 1-pip move on a standard lot equals exactly $10. This is because: 0.0001 × 100,000 = $10. For pairs where USD is the base (USD/JPY, USD/CAD), the pip value varies with the exchange rate.
- How do I find pip value for JPY pairs?
- JPY pairs use a pip size of 0.01 (not 0.0001), and the pip value fluctuates with the exchange rate. Use the Forex Pip Calculator to get an accurate pip value, then enter it here for your lot size calculation.
- How much risk per trade is appropriate?
- Most professional forex traders risk between 0.5% and 2% per trade. Beginners should start at 1% or below. At 1% risk, you can lose 100 consecutive trades before blowing up — giving you enormous margin to learn and improve.
- Can I use this calculator for non-forex instruments?
- This calculator uses the forex lot convention (standard/mini/micro lots). For stocks, use the Position Size Calculator instead, which calculates in shares rather than lots.