Updated 2026-07-25
A perpetual swap, usually just called a perp, is a futures contract with no expiry date. Because it never settles, it needs another mechanism to stay tethered to the underlying: the funding rate, a periodic payment between longs and shorts that makes the crowded side pay to keep its position.
Perps are where the majority of crypto leverage sits, which is why they matter for liquidation analysis. They are margined and marked continuously against a mark price derived from an index, they carry tiered maintenance margin requirements, and they liquidate positions automatically when equity runs out. Every liquidation level on a liquidation map belongs to a perp position somewhere. Full guide: perpetual futures explained.