Mark Price/Index Price/Order Price
1) Mark Price
To enhance contract market stability and reduce unnecessary liquidations during abnormal market fluctuations, we use the mark price to calculate users' unrealized P&L.
Mark Price = Spot Index Price + Basis Moving Average
Basis Moving Average = Moving Average (Contract Mid Price – Spot Index Price) = Moving Average ((Contract Best Ask Price + Contract Best Bid Price) / 2 – Spot Index Price)
The mark price takes into account both the spot index price and the moving average of the basis. The moving average mechanism smooths and filters short-term contract price fluctuations, reducing unnecessary liquidations caused by abnormal volatility.
2) Index Price
Coin-margined contracts use the USD index of the corresponding underlying asset. To ensure the spot index price reasonably reflects the fair spot market price of each cryptocurrency, we select 3 or more mainstream trading venues' trading pairs as index weight components for each contract currency, and design abnormal processing logic to ensure that when a single trading venue's price deviates significantly, the index fluctuation remains within a normal range.
Spot Index Price Calculation Logic:
a. Real-time acquisition of the latest transaction price and volume of all index component trading venue trading pairs for that currency
b. Trading venues under maintenance or with no updates to the latest transaction price and volume for a period of time are marked as invalid and do not participate in this calculation
c. Trading pairs priced in BTC are multiplied by the OKX BTC USD index to convert to USD price
d. Determine how many valid trading venues remain:
= 3 venues: Weight valid trading venue data equally (if a trading venue's price deviates more than 3% from the median of all trading venues' prices, that trading venue's price is calculated as median * 0.97 or median * 1.03)
= 2 venues: Weight valid trading venue data equally
= 1 venue: Directly use the remaining valid trading venue's price as the Index Price
3) Order Price
In limit orders and other trading order strategies, traders need to specify the buy or sell price for the trading order when placing it. The order will only be executed when the market price meets the order price, and this price is the order price.
Disclaimer
This article may contain content related to products that are not available in your region. This article is dedicated to providing general information only and is not responsible for any factual errors or omissions. The views expressed in this article are those of the author and do not represent the views of OKX. This article is not intended to provide any of the following advice, including but not limited to: (i) investment advice or investment recommendations; (ii) an offer or solicitation to buy, sell, or hold digital assets; or (iii) financial, accounting, legal, or tax advice. Holding digital assets (including stablecoins) involves high risk, may fluctuate significantly, or even become worthless. You should carefully consider whether trading or holding digital assets is suitable for you based on your financial situation. For questions regarding your specific circumstances, please consult your legal/tax/investment professionals. The information appearing in this article (including market data and statistics, if any) is for general reference only. Although we have exercised all reasonable care in preparing this data and these charts, we assume no responsibility for any factual errors or omissions expressed herein. © 2025 OKX. This article may be reproduced or distributed in its entirety, and excerpts of 100 words or less may also be used, provided such use is non-commercial. Any reproduction or distribution of the entire article must also prominently state: "Copyright © 2025 OKX, used with permission." Permitted excerpts must cite the article title and include attribution, such as "Article Title, [Author Name (if applicable)], © 2025 OKX". Some content may be generated or assisted by artificial intelligence (AI) tools. Derivative works or other uses of this article are not permitted.
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