Position Size & Risk Calculator
Turn your account risk, entry and stop into a position size, with estimated fees included.
Position size calculation method
- 01
Risk budgetAccount size multiplied by risk percentage.
- 02
Unit riskEntry-to-stop distance plus estimated fees.
- 03
Position sizeRisk budget divided by total risk per unit.
Educational estimate only. Slippage, gaps, taxes and broker rules can change actual outcomes.
About this tool
A position size calculator converts the maximum amount you are willing to lose into a trade quantity. It divides your account risk budget by the loss per share, coin or contract between entry and stop, including estimated fees.
How it works
Risk budget = account value × risk percentage. Unit risk = absolute entry-to-stop distance × contract multiplier, plus allocated fees. Position size = risk budget ÷ unit risk.
| Parameter | How it is used |
|---|---|
| Account size | Capital used to set the maximum loss budget. |
| Risk per trade | Percentage of the account allowed to be at risk. |
| Entry and stop | Price distance that defines loss per unit. |
| Fees and multiplier | Adjusts sizing for commissions and contract value. |
A $100 risk budget
A $10,000 account, 1% risk, $50 long entry, $48 stop, no fees and a multiplier of 1.
$10,000 × 1% = $100 risk. $50 − $48 = $2 risk per share. $100 ÷ $2 = 50 shares.
50 shares, $2,500 of exposure and $100 of planned price risk.
Exposure is not the same as risk. A gap below the stop can make the actual loss larger than $100.
How to use this tool
- Enter the account value and maximum risk percentage.
- Add the planned entry, stop price, fees and any contract multiplier.
- Use the calculated quantity and verify the total exposure before placing the order.
Frequently asked questions
What percentage should I risk per trade?
There is no universal percentage. Many traders choose a small fixed fraction that fits their strategy, drawdown tolerance and account rules, then apply it consistently.
Does the calculator work for short positions?
Yes. Position size depends on the absolute distance between entry and stop, so the same risk-budget method applies to long and short trades.
Why include fees in position sizing?
Commissions and other execution charges add to a losing trade. Including an estimate prevents the planned risk budget from being understated.