When it comes to evaluating the profitability of your position, multiple factors come into consideration. Here is how you can find out what your Break-Even Price is and whether you'll be in profit if you close your position.
Calculate PNL with Fees in Mind
When you calculate your Profit and Loss (PNL), you'll need to consider the fees associated with both Entry and Exit Orders, as well as Funding on Perpetual Contracts.
Unrealised PNL is determined by the formula:
Inverse Unrealised PNL = Number of lots * Multiplier * (100/Average Entry Price - 100/Exit Price)
Realised PNL is calculated as:
Realised PNL = Unrealised PNL - taker fee + maker rebate -/+ funding payment
Understanding Break-Even Price
The Break-Even Price is the price level at which the profit or loss on your trade is exactly zero. Above this price, your position is considered profitable, and below it, your position is in a loss. The Break-Even Price varies for each contract due to differences in fees. You can find the specific fees for each contract traded on BitMEX here.
Break-Even Price with Taker Fees
If you open and close an XBTUSD position using Market Orders, you'll pay 0.075% fee on both the Entry and Exit Order Value. To reach a Break-Even point in a profitable direction, your Exit Price should be 0.15% (2 * 0.075%) away from the Entry Price.
Break-Even Price with Taker and Maker Fees
If you pay the Taker Fee (0.075%) on the Entry Order but receive the Maker Rebate (0.025%) on the Exit Order, your Break-Even Price narrows to 0.05% (0.075% - 0.025%) in a profitable direction.
Break-Even Price with Maker Rebate
If you get the Maker Rebate (0.025%) on both Entry and Exit Orders, your Break-Even Price will be your Average Entry Price.
Finding Your Break-Even Price through the API
After opening a position, you can conveniently access your Break-Even Price by referring to the breakEvenPrice field on the Position endpoint. Keep in mind that this calculation assumes both Entry and Exit Orders pay the Taker Fee, and the position has not paid any Funding Fees.