The CoinDesk Ether Price Index (ETX) is the world’s leading reference for the price of ether, used by the largest institutions that are active in the crypto market. Asset allocators, asset managers, market participants and exchanges all rely on the ETX to provide a real-time, USD-equivalent spot rate for Ethereum’s native currency. The ETX is one of a suite of single- and multi-asset indexes offered by CoinDesk.*

Index licensing

To inquire about real-time feeds, historical data and benchmark licensing options for the CoinDesk Ether Price Index (ETX), other CoinDesk Indexes products and custom index development, contact us via indexes@coindesk.com or the form below.

ETX overview

The CoinDesk Ether Price Index (ETX) represents a real-time, USD-equivalent spot rate for ether, Ethereum’s native currency. The index value is algorithmically calculated once every second based on observed trading activity on leading exchanges, using the same methodology and infrastructure as the CoinDesk Bitcoin Price Index (XBX). In operation since 2014, the XBX is the benchmark for billions of dollars in assets under management and is the reference for hundreds of millions traded daily in the over-the-counter market. 

The ETX is designed as a reference rate that tracks liquidity while adjusting for deviations caused by anomalies and manipulation attempts at individual exchanges. While the precise formula underlying the index is proprietary, the key elements of the algorithm are outlined below.

Volume Weighting

Exchanges with greater liquidity receive a higher weighting in the index, increasing the ability to execute against the index in the underlying spot markets. Liquidity weighting also mitigates the impact of volume spikes during off-peak trading hours.

Price Variance Weighting

The index price reflects data points that are discretely weighted in proportion to their variance from the rest of the cohort. As the price at a particular exchange diverges from the rest of the data points, its influence on the index consequently decreases in real-time.

Inactivity Adjustment

The algorithm penalizes stale ticks on any given exchange. If an exchange does not have recent trading data, its weighting is gradually reduced, until it is de-weighted entirely. Similarly, once activity resumes, the corresponding weighting for that constituent is gradually increased until it reaches the appropriate level. 

Benefits of the CoinDesk Ether Price Index (ETX)

  • Manipulation resistant: Automatically discounts manipulation attempts and market anomalies.
  • Real-time: Responsive to market movements, while maintaining the overall stability of the rate.
  • Maximum replicability: Real-time weighting feeds are available for index replication in spot markets.
  • Reliable APIs: 99.9999% XBX Index uptime recorded since 2015.
  • Compliance: Index algorithm & governance based on IOSCO financial benchmark framework.
  • Fully auditable: Historical exchange prices and weightings stored for every data point.
  • The recognized market standard: Widely recognized as the highest-performing index for NAV calculation, derivatives and OTC trading.

Live data

For live prices and updates, visit TradeBlock, our index calculation agent subsidiary.

* These indexes are products for financial institutions, and are separate from the prices that CoinDesk publishes on coindesk.com.