Dear HTX Users:
To help users better understand the pricing mechanism of futures products, the calculation rules for the futures Index Price are detailed below:
I. Definition of Index Price
The Index Price represents the spot market price of the underlying asset. Since prices may vary slightly across different exchanges, the Index Price is designed to provide a stable reference price. To ensure the Index Price remains reliable and stable, it is calculated as a weighted average of spot prices from major cryptocurrency exchanges.
II. Selection Criteria for Constituent Exchanges
The constituent exchanges selected by HTX must meet the following criteria:
1. Compliance: Possess a solid track record of compliant operations;
2. Liquidity: Maintain sufficient market depth and trading volume for spot trading pairs;
3. Stability: Offer stable and reliable API interfaces with timely price data updates;
4. Credibility: Command high recognition and credibility in the global crypto market.
Currently, HTX Index Price constituent exchanges include (subject to the real-time parameters displayed on each crypto's specific page):
Binance, OKX, Coinbase, Kraken, Bitstamp, Bybit, Bitget, and other major platforms.
III. Index Price Calculation Method
1. Basic Calculation Formula
The Index Price is calculated using a multi-exchange weighted average method: Index Price = Σ (Constituent Exchange Price × Corresponding Weight) ÷ Σ Weight.
2. Weight Allocation Rules
Weights are dynamically adjusted based on the 24-hour spot trading volume and market depth of each constituent exchange, and are updated daily at 00:00 (UTC).
IV. Index Anomaly Handling
1. Significant Price Deviation from a Single Exchange
Scenario 1: More than 2 valid exchanges remain in the Index Price calculation (Median Deviation Correction of ±3%)
When the absolute deviation of a certain exchange's price relative to the sample median is ≥ 3%, that exchange's price will be corrected to:
- Median × (1 + 3%) (when the price is above the median);
- Or Median × (1 - 3%) (when the price is below the median).
The corrected price will then be factored into the Index Price calculation.
Example:
Assume the BTC price quotes from 6 exchanges are 518, 500, 501, 502, 503, and 504 USDT respectively (for illustrative purposes, this example assumes equal weight for each exchange).
① Median = 502.5 USDT
② Deviation = 3.08% > 3%, correction triggered
③ Corrected price = 502.5 × 1.03 = 517.57 USDT
④ Index Price = (517.57 + 500 + 501 + 502 + 503 + 504) / 6 = 504.59
Scenario 2: Only 2 valid exchanges remain in the Index Price calculation
(This occurs when there are originally only 2 exchanges in the Index Price calculation, or when some exchanges are temporarily excluded due to missing market data feeds.)
If the price deviation between the two platforms is > 25%, the Index Price will anchor to the exchange with the smaller deviation relative to the last recorded Index Price (the other exchange will be treated as an anomaly, i.e., a "fat-finger" error).
Deviation formula = ∣P−R∣/R×100%.
Scenario 3: The Index Price is based on only 1 exchange
(This occurs when all other exchanges have been excluded due to anomalies.) If the price of the sole exchange deviates from the previous Index Price by > 25%, it is determined to be an abnormal price (“fat-finger” error), and the Index Price retains the previous price.
Deviation formula = ∣P−R∣/R×100%.
V. Risk Reminder
1. The Index Price serves only as a reference for futures pricing and may deviate from the actual execution prices in the spot market.
2. Before participating in futures trading, users should fully understand the correlation between the Index Price, Mark Price, and the liquidation mechanism.
3. Futures trading carries high risks; please participate rationally based on your own risk tolerance.
If you have any questions, please contact HTX Online Customer Service or visit the Support Center.
VI. Exchange Rate Calculation Rules
The exchange rate used for USDT-M futures is based on data from HTX's official exchange rate API and is updated once per minute.
https://api.huobi.pro/general/exchange_rate/list
If you have any questions, please contact our Online Customer Service. Our team is available 24/7 to assist you.
Thank you for your continued support and trust. We will continue to provide high-quality products and services to you, just as we always have.
HTX Team
May 25, 2026
