The mark price is determined by the real-time index price and the upcoming funding rate, reflecting the current fair price of the futures. The mark price is used to calculate the unrealized PnL of the position and trigger liquidations.

The index price is calculated based on the weighted average price of an asset across major spot exchanges. It reflects the global market value of the asset and serves as the primary reference for mark price and funding rate calculations.

Long and short position holders will incur funding fees every 8 hours. If the funding rate is positive after settlement, the longs will pay the shorts. If the funding rate is negative, the shorts will pay the longs. Note: The system will calculate the funding fee during settlement based on the position value. The funding fee will be deducted from the paying user and then sent to the recipient. However, if the paying user's positions are liquidated or if there is insufficient margin in isolated margin mode, the recipient may not receive the full amount. Funding fee = position value × funding rate.