How funding quietly kills positions
On perpetual futures there's no expiry, so the exchange uses a funding rate to keep the perp price near spot. Every 8 hours, if funding is positive, longs pay shorts; if negative, shorts pay longs — a percentage of your full position size, not your margin. At 20x leverage a 0.05% funding charge is 1% of your margin every 8 hours. Hold a crowded trade for days and funding alone can drain you before price ever hits your liquidation. This calculator pulls the live rate per symbol so you can see the real carrying cost before you hold.