What is Mark price?

The mark price is the price a perpetual futures venue uses to value every open position. It is usually close to the last traded price, but it is built to be harder to push around. A single market order in a thin book can print a trade far from where the market really is; if liquidations ran on that print, one wick could close thousands of positions that were fine a second earlier. The mark price exists so that does not happen.

Venues build it from several inputs and take something like a median. Hyperliquid documents its recipe: the median of three prices, namely its oracle price adjusted by a 150-second moving average of the gap between Hyperliquid’s own mid price and the oracle; the median of the best bid, best ask and last trade on Hyperliquid; and a weighted median of perp mid prices on Binance, OKX, Bybit, Gate and MEXC. It updates about every three seconds and is used for margining, liquidations, take-profit and stop-loss triggers and unrealized PnL. On Lighter, every margin requirement is position size times mark price times the market’s margin fraction.

For a trader this has three practical consequences. The unrealized PnL on a position card is marked, so it can differ from what the last trade on the chart suggests. A stop or take-profit that triggers on mark can fire at a moment the chart does not show as special. And a liquidation happens when the mark price, not a stray print, crosses the liquidation price, which is why a sharp wick on one exchange often leaves positions untouched while a sustained move does not.

The mark price is also the right number for a portfolio total. TrueHold values perp positions on Hyperliquid, Lighter and connected exchanges at each venue’s mark price, so the PnL in the total matches what the venue itself would use to decide whether a position survives.