To avoid spikes and unnecessary liquidations during periods of high volatility, ONUS Pro uses Last Traded Price and Mark Price.

Mark Price

For perpetual contracts, the Mark Price refers to a global Spot price index plus a decaying funding basis rate. Mark Price can be considered to reflect the real-time Spot price on the major exchanges. We use Mark Price as a trigger for liquidation and to measure unrealized profit and loss, but this doesn’t affect a trader’s actual profit & loss. Only when the Mark Price reaches a trader’s liquidation price is the trader’s position then liquidated.


Calculation of Mark Price

Mark Price = Median (Price 1, Price 2, Last Traded Price)

Price 1 = Index Price * [1 + Last Funding Rate * (Time Until Funding / 8)]

Price 2 = Index Price + Moving Average (5 minute Basis)

Moving Average (5-minute Basis) = Moving Average [(Bid1 + Ask1)/2 − Index Price], which measures every second in a 5-minute interval.

In the following scenarios, ONUS Pro will adjust the criteria for selecting the mark price to be used for calculation:

  • If the index price of any Spot exchange is abnormal or data cannot be obtained, and thus the total weight of the remaining exchanges is less than 50%, the mark price will be calculated based on the last traded price on the ONUS Pro platform.
  • Due to factors such as index price distortion, there is insufficient data to calculate the 5 minute moving average. In this scenario, the mark price will be calculated by ONUS Pro's last traded price.
  • If the state of Abs(Index price - Last Price)/Index price > 1% lasts for more than 5 minutes, the price of the Spot market and the Derivatives market is considered to be deviating, and the Mark price is calculated as Price 2.


  • ONUS Pro will use the optimal Mark Price to reduce the risk of trader’s position being volatile markets.
  • ONUS Pro reserves the right to update the Mark Price selection criteria in real time according to market conditions without prior notice.

Last Traded Price

Last Traded Price refers to the latest transaction price the contract was traded at. In other words, the last trade in trading history defines the Last Traded Price. It’s used for calculating your Closed P&L. Last Traded Price is always anchored to the Spot price using the funding mechanism. This is why the price on ONUS Pro is unlikely to deviate significantly from the Spot market price.


In a fluctuating market, the Last Traded Price on ONUS Pro may temporarily deviate from the Mark Price. This may cause an immediate unrealized profit or loss right after order execution. Kindly note that this is not a real profit or loss, but please be reminded to keep an eye on the distance between Liquidation Price and Mark Price.