Effective April 27, 2026, CME Group will launch CME FX Tape+ to provide centralized reference prices and a comprehensive view of FX market liquidity from its transparent central limit order book (CLOB) marketplaces, including FX futures, EBS Market, FX Spot+‌, and FX Link. The new CME FX Tape+ will provide FX market participants a unique view of centralized spot and forward liquidity, enabling them to better manage their trading costs and benchmark their strategies.

With this release, CME FX Tape+ will disseminate reference data calculated at approximately 250-millisecond intervals via WebSocket API. The near real time data will enhance market participants confidence in analyzing their total cost and trade execution strategies.

Contents

Revision History

Key Events and Dates

Testing and Certification

Certification is not required for CME FX Tape+ over WebSocket API.

Product Offerings

The offering will initially cover 10 major currencies and will include a composite 'true' spot mid-price, combining liquidity, trades, and mid-rates from across these venues.

Onboarding and Entitlements

CME FX Tape+ uses OAuth, an open protocol that supports secure authorization in a simple, standard method and decouples authentication from authorization. More details about OAuth API ID authorization and authentication are available in Client API Service Adoption Using OAuth 2.0 Protocol.

To access the CME FX Tape+, client API IDs must be entitled. Request access from the CME Group Market Data API self-service onboarding page or contact Global Account Management (GAM).

Connectivity

CME FX Tape+ Over WebSocket API is a bi-directional communication allowing clients access to reference data in real-time in JSON format.

Once clients have completed onboarding and granted entitlements they can access the CME FX Tape+ Over WebSocket API endpoints. WebSocket API supports WSS connections over the internet.

OWASP Compliance

The APIs are hosted on Google Cloud and protected by Google Cloud Armor with preconfigured Web Application Firewall(WAF) rules leveraging the OWASP Top 10 rules.

Client systems should utilize the OWASP Top 10 rules. 

Message Specifications

The business message specifications for CME FX Tape+ over WebSocket are available below.

Messaging Summary

The diagram below shows the message flow for CME Market Data Over WebSocket API.

WebSocket Connection

Login Status Messages

Upon a WebSocket connection, CME FX Tape+ Over WebSocket API sends one of the following login status messages.  

Message Requests

A subscription message allows client systems to recover and subscribe to a product code. A subscription is sent after a successful login. Subscription requests and book states are reset at session disconnection. Therefore, subscriptions must be re-established after reconnection and a successful login.

Subscription Message

Additional Considerations

Sequence Number

Sequence Number (field name sequenceNumber) is a unique number per each CME to client message. Each topic has its own separate set of sequence numbers that increment sequentially with each message and reset weekly. 

Heartbeat

Heartbeat messages are generated by the API every 10 seconds, independently for each authenticated socket connection in periods of no activity. They allow the connection to remain open when no market data messages are being published. The messageType for the heartbeat is "HEARTBEAT.”  Users of the API should monitor for these heartbeat messages so that they can identify if a WebSocket connection has gone stale. If a connection to the API is open but no heartbeat messages are detected within the ranges specified, this indicates that the WebSocket connection is stale and that clients should close the active connection, open a new connection, and re-subscribe for market data.

System Recovery Processing

In the event of a CME WebSocket Market Data failure, client systems must reestablish a connection and re-subscribe via request messages. 

Trading Schedules

The Real Time CME FX Tape+ (Mid Rate) product is available throughout the week with varying open and close timings across markets of its constituent inputs.

Sunday through Friday, 4:00 p.m. – 5:00 p.m. Central Time (CT) with a 60-minute break at 4:00 p.m. CT.

CME FX Market

Sunday through Friday, 4:00 p.m. – 5:00 p.m. Central Time (CT) with a 60-minute break at 4 p.m. CT.

EBS FX Market

See CME Group Holiday and Trading Hours.