How profit and loss are calculated
Long: (exit − entry) × shares − fees. Short: (entry − exit) × shares − fees. The return is the net result divided by the position cost (entry × shares).
Commissions are charged on both orders — the buy and the sell — and you choose how your broker charges them: a percentage of the order value (for example 0.04%), a fixed amount per order or an amount per share, with an optional minimum. With a percentage, the sell commission depends on the exit price.
The break-even exit price is the price at which both commissions are covered and the result is zero. Spreads, currency conversion and taxes are not included.