EdgeHTML

EdgeHTML is a proprietary rendering engine developed by Microsoft to power the Edge web browser. It was introduced with the initial Edge release in 2015 as a successor to Internet Explorer and is a fork of the Trident engine used by IE. EdgeHTML was designed to render HTML and CSS with a focus on modern standards support while integrating with Windows, including the Chakra JavaScript engine.

EdgeHTML aimed to deliver faster page rendering, improved security, and better support for contemporary web features than its Internet Explorer predecessor, while preserving Windows-specific user experiences such as the Edge user interface and Reading View. It represented Microsoft’s effort to provide a more standards-focused, modern browser engine within a Windows-centric stack.

In practice, EdgeHTML powered Edge until the transition away from the legacy browser. In 2018, Microsoft announced a switch to a Chromium-based engine, and Edge 79, released in 2020, adopted the Blink rendering engine. Since then, EdgeHTML has been deprecated and is no longer used in current Edge releases.

EdgeHTML’s role was tied to a Windows-integrated, proprietary stack that included the Chakra JavaScript engine. It was not open source and remained largely Windows-centric during its lifespan. With the move to Chromium, Microsoft aimed to improve cross-platform compatibility and alignment with the broader web ecosystem.