Position size calculator

Size the trade from the loss you can afford.

Calculator

Enter your numbers.

Choose a preset, then confirm its editable contract specification against your broker.
Currency used for the account balance and risk budget.
Current account equity.
Maximum account equity to lose on the trade.
Planned trade entry price.
Price where the trade exits for a loss.
Underlying units represented by one share, lot, contract, or coin quantity.
Smallest position-size increment accepted by the broker or venue.

Worked example

A US stock trade with a fixed percentage of the account at risk and a stop placed below the entry. These are the calculator's default inputs and the result it returns for them.

InstrumentEquity · US stock or ETF
Account currencyUSD
Account balance25,000 USD
Risk per trade1%
Entry price100 USD
Stop price98 USD
Contract size1 units / share
Size increment1 shares
Position size125 shares
Cash risk$250.00
Position value$12,500.00

Rounded down to the 1 share increment. Verify the contract specification with your broker; gaps, slippage, fees, and margin are excluded.

Questions

How is position size calculated?
The calculator takes your risk budget, which is balance times risk per trade, and divides it by the loss per unit at your stop. The result is rounded down to your size increment.
How do I read the result?
Position size is the quantity to trade. Cash risk is what you lose if the stop fills at your stop price. It can sit slightly below your budget because of rounding.
What is a common mistake?
Using the wrong contract size or tick value. Check the contract specification with your broker, and remember that gaps, slippage and fees can make the real loss larger.

Your next trade deservesproof.