Position size under FTMO rules
A normal position-size calculator ignores the two numbers that end challenges. This one does not.
Lots for this trade
2.50
Risking $500 if the stop is hit.
Daily buffer left
$5,000
Max daily loss 5% of $100,000
Total buffer left
$10,000
Max loss 10% of $100,000
Buffer used if stopped
10%
Share of the tighter limit this one trade consumes.
- A 10% safety margin is kept for spread, slippage and commission. Stops are not guaranteed fills.
- Rule percentages are measured against the initial balance. Last checked 2026-10-16. Confirm the current rules on FTMO.
Why the cap matters
FTMO's maximum daily loss and maximum loss are measured in money against your initial balance and include floating losses. A trade sized at "1% risk" is fine on a fresh day. The same trade after a losing morning can take you through the daily limit on a single stop-out, and a breach ends the attempt. The calculator looks at both buffers, picks the tighter one, keeps a 10% margin for spread and slippage, and sizes to that.
How to use it daily
- Enter today's P&L, including open trades, and your equity versus the starting balance.
- Enter the risk you want, your stop distance and the pip value for the symbol.
- Trade the lot size shown. If it says zero, stop for the day.
If you find the capped size is regularly below what you want, the fix is fewer trades or a smaller account, not a bigger stop.