Position size calculator

Most people choose a size that feels right and find out afterwards what it risks. This does it the other way round — you say what you are willing to lose, and the size falls out of it. It is the single habit that separates accounts that survive a bad month from accounts that do not.

0.20 lots

risking $100.00 of $10,000.00

Show the working +
  1. 1.00% of $10,000.00 = $100.00 you are willing to lose.
  2. A pip is worth $10.00 per lot, so a 50 pip stop costs $500.00 per lot.
  3. $100.00 ÷ $500.00 = 0.200 lots.
  4. Rounded DOWN to 0.20 — rounding up would break the limit you just set.
  5. That position controls $23,249.80 of EUR.

Prices shown are our last stored reading and are indicative only. Contract sizes follow the standard market conventions and are printed above the calculator; your account’s own specification is what applies to a real position. Nothing here is a recommendation.

Why it rounds down

The arithmetic rarely lands on a size you can actually place. Rounding up would quietly exceed the limit you just set, so this always rounds down to the nearest 0.01 lot and then tells you what that size really risks.

Sometimes the answer is zero. A $100 account with a 200 pip stop cannot risk 1% and place a trade, because the size required is smaller than the minimum. That is a real answer, not an error — the honest response is that the trade does not fit the account.

On the risk percentage

One to two percent per trade is the figure most professionals work to, and it is not conservatism for its own sake. At 2% a run of ten losses — which happens to everyone — costs about a fifth of the account. At 10% the same run is most of it, and what remains cannot recover the rest.

The percentage is also what makes a losing run survivable psychologically. A loss that hurts changes how you take the next trade, and traders who size too large stop following their own rules long before they run out of money.

The stop comes first

Choose the stop from the chart — where the idea is wrong — and then let the size follow. Doing it the other way round, choosing a size and then placing the stop where the loss feels tolerable, puts the stop somewhere the market has no reason to respect.

Common questions

What risk percentage should I use?
Most experienced traders use 1–2% of the account per trade. Lower is defensible. Higher needs a specific reason, and "I am confident about this one" is not one — the trades people feel most confident about are not measurably more likely to work.
Should the percentage be of balance or equity?
Equity, if you already have positions open, since that is the money actually available. With no open positions the two are the same.
Why does the answer change when I change the pair?
Because the pip value differs. A 50 pip stop on gold and a 50 pip stop on EUR/USD are different amounts of money, so they support different sizes.
What if the calculator says zero lots?
The trade does not fit the account at that stop and that risk level. Widen the account, choose a setup with a tighter stop, or skip it. Placing the minimum size anyway means accepting a larger percentage risk than you decided on.

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