Mark price is a reference price used by perpetual venues for unrealized PnL and often for liquidation triggers. It is typically derived from a basket of spot prices and/or a smoothed mid, rather than the last trade alone.
Understanding mark price
Using mark price reduces the chance that a single thin print liquidates users unfairly. Funding calculations may also reference mark or index components depending on venue design.
ApeX Omni funding history responses include mark/price fields traders can use when reconstructing carry and PnL.