Tool

Position Size Calculator

Size a trade so that if the stop is hit, you lose the amount you planned, fees included. Then see what each target pays after fees.

Your trade

Direction

Account balance

$

Risk per trade

%

Stop distance

%

Entry price (optional, for stop and target prices)

$

Exchange fees

Maker fee applies to the take-profit limit order; taker fee to the market entry and stop.

Maker fee

%

Taker fee

%

Slippage (optional, worse fill on entry and stop)

%

Result

Position size $0.00 0% of balance

Max loss at stop (fees in)$0.00

Stop price–

Units–

Fees if stopped out$0.00

Target	Price	Net profit	Net R

Net profit is after the entry fee and the exit fee. “2R lock” is an early exit at 2R with a stop order (taker fee), used when a trade reaches 2.5R and fades.

Why size by fees?

If you put your whole balance into a trade with a 2.5% stop, the stop alone costs 2.5%, but the entry and exit fees push the real loss past 4% at entry-tier fees. Sizing the position down so that stop, fees and slippage add up to your risk keeps every loss the size you planned. At a 2.5% stop and Kraken’s entry-tier fees, that works out to about 61% of the balance.

This is the sizing behind the Plimoth Harbor rules: 2.5% risk per trade, targets of 1:2 to 1:4, a profit lock at 2R, and two losses in a row ends the session.