HTML Guides
Learn how to identify and fix common HTML validation errors flagged by the W3C Validator — so your pages are standards-compliant and render correctly across every browser. Also check our Accessibility Guides.
The X-UA-Compatible header tells Internet Explorer which rendering engine to use for a page. Setting it to IE=edge instructs IE to use the highest available standards mode, ensuring the best compatibility and avoiding legacy rendering quirks. The ,chrome=1 directive was an addition that told browsers with the Google Chrome Frame plugin installed to use Chrome's rendering engine instead of IE's. Google discontinued Chrome Frame in 2014, and the W3C validator only accepts IE=edge as a valid value for this header.
Including the deprecated chrome=1 directive causes a validation error and serves no practical purpose on modern websites. No current browser recognizes or acts on it, so it's dead code that only creates noise in your markup.
The fix is straightforward: remove ,chrome=1 from the content attribute, leaving only IE=edge.
Examples
Incorrect
The following triggers the validation error because of the ,chrome=1 suffix:
<metahttp-equiv="X-UA-Compatible"content="IE=edge,chrome=1">
Correct
Simply use IE=edge as the sole value:
<metahttp-equiv="X-UA-Compatible"content="IE=edge">
Full document example
If you include this meta tag in a complete HTML document, place it early in the <head>:
<!DOCTYPE html>
<htmllang="en">
<head>
<metacharset="utf-8">
<metahttp-equiv="X-UA-Compatible"content="IE=edge">
<title>My Web Page</title>
</head>
<body>
<h1>Hello World</h1>
</body>
</html>
Server-side configuration
If you set X-UA-Compatible as an HTTP response header rather than a meta tag, apply the same fix there. For example, in an Apache .htaccess file:
<IfModule mod_headers.c>
Header set X-UA-Compatible "IE=edge"
</IfModule>
In Nginx:
add_header X-UA-Compatible "IE=edge";
Is this meta tag still needed?
With Internet Explorer reaching end of life, the X-UA-Compatible meta tag itself is largely unnecessary for new projects. If your site no longer needs to support IE, you can safely remove the tag entirely. If you do keep it for legacy support, ensure the value is exactly IE=edge with no additional directives.
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