A perpetual does not have one price, it has three. The last price is what you see on the chart and what fills your orders. The index price is the fair spot value, drawn from several exchanges, and it drives funding. The mark price is a smoothed fair value, and it is the one that calculates your unrealised profit, your margin, and your liquidation. Confusing them is why traders think their profit vanished or their liquidation was rigged. This piece separates the three, explains the basis that connects them, and shows why the number that closes your position is deliberately not the number flashing on the tape.

Tag: Mark Price

Mark Price vs Index vs Last Price, and Basis Explained