If liquidations were calculated from the last traded price on a single venue, a brief wick — one large order in a thin moment — could close out positions that the wider market never went against. The mark price exists to prevent that. It is derived from an index of spot prices across several exchanges, adjusted for the contract's funding basis, and it is what unrealised profit, loss and the liquidation trigger are all measured against.
This is why a position can survive a visible spike through its liquidation level: the trade printed, but the mark price never followed. It also means the liquidation price shown in a trading interface refers to the mark, not to the number ticking in the order book.
Why was I not liquidated when the price touched my liquidation level?
Liquidation runs off the mark price, which is an index across venues, not the last trade on the one you are looking at. A wick on a single exchange often does not move the mark.
Last updated October 17, 2026