Mark price
A smoothed reference price, built from the index price, used to value positions and trigger liquidations.
The mark price is the reference price an exchange uses to value open positions and decide when they are liquidated. It is usually based on the index price plus a smoothed basis, rather than the last traded price. The design makes it harder for a single large trade or a brief spike on one venue to trigger liquidations.
On our site, the mark price is shown alongside the last trade. A gap between the two can signal thin liquidity or a momentary dislocation. Check which price a number refers to before comparing profit and loss across sources.
Traders care because liquidation happens at the mark price, not the last trade. A position can look safe on a last-trade chart and still be liquidated if the mark price crosses its threshold.
Worked example (illustrative numbers, not real data): the last trade briefly prints at 49,200 on one venue, but the index is 50,000 and the smoothed basis is 0.1 percent. The mark is about 50,050, so a long with a liquidation level at 49,500 is not liquidated by the spike.