Free tool

Position size calculator

Enter your balance, the risk you are willing to take and where your stop sits. It returns the position size that keeps the loss at that stop equal to the risk you chose.

Instrument

Trade

USD
%
lots
USD
Position size
—
Enter balance, risk %, entry and stop to size the trade.
How it works

What the position size calculator does

risk amount = balance x risk %size = risk amount / (value per pip per lot x stop distance in pips)

The result is then rounded down to the smallest increment your broker actually accepts, so the size you are given always risks a little less than your limit and never more.

Example

A worked example

  1. 01Balance $10,000, risking 1%, so $100 is on the line.
  2. 02Long EURUSD from 1.0850 with the stop at 1.0800, a 50 pip stop.
  3. 03One standard lot of EURUSD moves $10 per pip, so 50 pips costs $500 per lot.
  4. 04$100 / $500 = 0.20 lots.
Questions

Worth knowing

What risk percentage should I use?
Most traders working with a fixed-percentage model land between 0.5% and 2% of the account on any one trade. The number matters less than holding it steady. Sizing by feel is what turns one bad trade into a bad month.
Does this work for futures, indices and crypto as well as forex?
Yes. Pick the instrument at the top of the calculator and the contract specification comes with it, so a NASDAQ future is sized on its tick value and Bitcoin on its unit value rather than on a pip.
Why is my size rounded down?
Because your broker only accepts certain increments. Rounding up would quietly put more at risk than you asked for, so the calculator always rounds down and shows you the risk the rounded size actually carries.
Where do costs come in?
Add your round-trip commission per lot and it is taken out of the risk budget before the size is worked out, which is why a costed size is slightly smaller than a free one.
More tools

The other calculators

The calculation is the easy half

Sizing a trade correctly once is arithmetic. Doing it on every trade, then being able to look back and see whether it made you any money, is the part that needs a journal. DT Terminal verifies the trades your broker sends on Pro and shows you whether the sizing paid.

Start freeSee all six calculators