Lot Size Calculator
Calculate optimal position size in lots and units based on account balance, risk tolerance, and stop-loss distance
Calculation Results
If your trade hits your 20-pip stop loss, your loss will be approximately 100.00 USD (1% of equity), before slippage, spreads and commissions.
Risk Warning: Trading leveraged forex and CFDs carries a high degree of risk to your capital. Never risk more money than you can comfortably afford to lose. Always verify your broker's specific lot contract size and margin requirements before opening live market positions.
What is Lot Size & Position Sizing in Forex?
In foreign exchange and CFD markets, position sizing refers to the exact volume of currency units or lots you purchase or sell on a given trade. Your lot size is the single most critical variable determining how much capital you gain or lose for every pip the market moves.
A standard trade is measured in standardized batches called lots:
- Standard Lot (1.00): 100,000 units of base currency (~$10.00/pip on EUR/USD).
- Mini Lot (0.10): 10,000 units of base currency (~$1.00/pip on EUR/USD).
- Micro Lot (0.01): 1,000 units of base currency (~$0.10/pip on EUR/USD).
Amateur traders often trade a static lot size (such as always entering 1.0 lot) regardless of how far their stop loss is. Professional traders do the exact opposite: they determine where their technical stop loss must be placed first, and then calculate the exact lot size required so their dollar risk remains strictly within their 1% or 2% limit.
Assuming a fixed $100 USD Risk (1% on $10k account) on EUR/USD:
How to Use the Lot Size Calculator
Calculate your exact position size in four quick steps before clicking buy or sell.
Select Currency Pair
Choose from forex majors, minors, exotic cross pairs, or precious metals like XAU/USD (Gold), XAG/USD (Silver), XPT/USD (Platinum) and XPD/USD (Palladium).
Set Account Equity
Enter your total available account balance and choose your base account currency (USD, EUR, GBP, JPY, AUD, CAD, CHF or NZD).
Define Risk %
Specify the percentage of your equity you are willing to risk on this setup (recommended 1% to 2% maximum).
Enter Stop Loss (Pips)
Input your planned stop-loss distance in pips based on your chart structure, support/resistance, or ATR.
The Position Sizing Formula Explained
Here is the exact mathematical sequence professional trading desks use to determine position sizing:
Cash Risk Amount
Calculate maximum monetary risk from your account balance:
Example: $10,000 balance × (1% ÷ 100) = $100 USD
Pip Value per Lot
Value 1 pip per contract, then convert it into your account currency:
EUR/USD = $10.00/pip (no conversion) | USD/JPY @ 155 = ~$6.45/pip (JPY→USD)
Recommended Lots
Divide cash risk by total monetary stop-loss distance:
$100 ÷ (25 pips × $10.00) = 0.40 Lots
Real-World Calculation Walkthroughs
The Mathematics of Drawdown: Why 1% Risk Saves Traders
When you suffer losses, the return required to get back to breakeven increases exponentially, not linearly. Strict position sizing prevents catastrophic account damage.
| Account Drawdown | Remaining Capital on $10,000 | Gain Needed to Breakeven | Account Survival Risk Level |
|---|---|---|---|
| 10% Loss | $9,000 | +11.1% Gain | Safe & Manageable |
| 20% Loss | $8,000 | +25.0% Gain | Moderate Recovery Effort |
| 30% Loss | $7,000 | +42.9% Gain | Significant Psychological Stress |
| 50% Loss | $5,000 | +100.0% Gain | Extreme Risk of Complete Ruin |
| 75% Loss | $2,500 | +300.0% Gain | Near Impossible Recovery |
Common Position Sizing Mistakes to Avoid
Fixed Lot Trading
Trading 1.0 lot on every trade regardless of stop-loss size causes wide-stop trades to risk huge amounts of capital while tight-stop trades risk almost nothing.
Over-Leveraging on Prop Challenges
Most prop firm evaluation rules impose a 4% to 5% maximum daily loss limit. Risking 2% or 3% on a single position gives you virtually zero buffer against normal market noise.
Ignoring Metal Contract Sizes
Spot Silver (XAG/USD) is typically 5,000 oz per standard lot ($50/pip), while Gold (XAU/USD) is 100 oz ($10/pip). Treating metals like standard forex pairs results in massive over-sizing errors.
Frequently Asked Questions About Lot Size & Risk
Everything you need to know about calculating lot sizes, managing risk, and preserving capital.
Turn Every Lot Traded into Cash Rebates
Every time you execute a properly sized position, you generate commission revenue for your broker. Through PaidRebate, link your broker account and receive cash rebates on every traded lot—paid directly to your wallet every month, win or lose.