Advanced Position Sizing Calculator

Model trade size using risk and stops. Test fees, leverage, slippage, and allocation before entry. Protect capital with smarter sizing across changing market conditions.

Calculator Inputs

Use the fields below to size a position by risk budget, then test whether allocation and leverage limits still keep exposure within your rules.

Example Data Table

Scenario Balance Risk % Entry Stop Target Fee % Leverage
Large cap equity 50,000 1.00 125.00 118.00 145.00 0.15 1.00
Index CFD 20,000 0.75 4,850.00 4,790.00 4,980.00 0.05 5.00
Commodity future 80,000 1.25 72.40 69.80 78.90 0.04 4.00

Formula Used

1. Risk budget

Use either a fixed money amount or a balance percentage. If no fixed amount is entered, the model uses Account Balance × Risk %.

2. Effective risk per unit

|Entry − Stop| + Slippage Cost + Round-trip Fees, then multiply by contract multiplier and currency conversion rate.

3. Raw units

Risk Budget ÷ Effective Risk per Unit. This gives the theoretical maximum size before lot rounding.

4. Final units

The model rounds raw units down to the nearest tradable lot, then applies the allocation cap so position value stays within your exposure rule.

5. Key supporting outputs

Margin required equals Position Value ÷ Leverage. Reward to risk ratio equals Gross Reward ÷ Total Risk.

How to Use This Calculator

  1. Enter your account balance and choose either risk percent or a fixed currency risk amount.
  2. Set entry, stop, and optional target prices for the planned trade.
  3. Add slippage, fees, leverage, lot size, and any contract multiplier used by your broker or market.
  4. Set a maximum allocation percent to prevent oversized exposure, even when the stop is tight.
  5. Click the calculate button. The result block appears below the header and above the form.
  6. Review final units, total risk, margin required, exposure percent, and reward to risk before placing any order.

Frequently Asked Questions

1. What is position sizing?

Position sizing decides how many units you can buy or sell while keeping risk inside a chosen limit. It helps protect capital across many trades.

2. Why include fees and slippage?

Ignoring trading costs can oversize a position. Including slippage and fees gives a more realistic risk-per-unit number and usually reduces hidden exposure.

3. What happens if I enter both risk percent and fixed risk?

The calculator prioritizes the fixed risk amount. This makes it useful when you want the same cash risk on every trade regardless of account size.

4. Why is my final size smaller than raw units?

That usually happens because lot rounding or the maximum allocation cap reduced the trade. The summary shows which constraint controlled the final size.

5. Can I use this for short positions?

Yes. If your stop is above the entry price, the tool labels the setup as short. Risk still uses the absolute distance between entry and stop.

6. What does contract multiplier mean?

Some products represent more than one underlying unit per contract. The multiplier scales both risk and position value to reflect the true exposure.

7. Why is leverage shown separately from risk?

Leverage changes margin required, not stop distance. A leveraged trade can still be risky if the position value or stop distance is too large.

8. Is reward to risk enough for trade selection?

No. It is helpful, but you should also judge win probability, liquidity, correlation, market conditions, and whether the setup fits your strategy.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.