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List of default Accept values

Default values

These are the values sent when the context doesn't give better information. Note that all browsers add the */* MIME Type to cover all cases. This is typically used for requests initiated via the address bar of a browser, or via an HTML <a> element.

User Agent Value Comment
Firefox text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
 
This value can be modified using the network.http.accept.default parameter.
Safari, Chrome

application/xml,application/xhtml+xml,text/html;q=0.9, text/plain;q=0.8,image/png,*/*;q=0.5

source
Safari 5

text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8

This is an improvement over earlier Accept headers as it no longer ranks image/png above text/html
Internet Explorer 8 image/jpeg, application/x-ms-application, image/gif, application/xaml+xml, image/pjpeg, application/x-ms-xbap, application/x-shockwave-flash, application/msword, */* See IE and the Accept Header (IEInternals' MSDN blog).
Edge */*  
Opera text/html, application/xml;q=0.9, application/xhtml+xml, image/png, image/webp, image/jpeg, image/gif, image/x-xbitmap, */*;q=0.1  

Values for an image

When requesting an image, like through an HTML <img> element, user-agent often sets a specific list of media types to be welcomed.

User Agent Value Comment
Firefox */* (since Firefox 47)
image/png,image/*;q=0.8,*/*;q=0.5 (before)
This value can be modified using the image.http.accept parameter.
Safari */*  
Chrome image/webp,image/*,*/*;q=0.8 Was */* before the support for webp
Internet Explorer 8 or earlier */* See IE and the Accept Header (IEInternals' MSDN blog)
Internet Explorer 9 image/png,image/svg+xml,image/*;q=0.8, */*;q=0.5 See Fiddler is better with Internet Explorer 9 (IEInternals' MSDN blog)

Values for a video

When a video is requested, via the <video> HTML element, most browsers use specific values.

User Agent Value Comment
Firefox earlier than 3.6 no support for <video>  
Firefox 3.6 and later audio/webm, audio/ogg, audio/wav, audio/*;q=0.9, application/ogg;q=0.7, video/*;q=0.6; */*;q=0.5 See bug 489071
Chrome */*  
Internet Explorer 8 or earlier no support for <video>  

Values for audio resources

When an audio file is requested, like via the <audio> HTML element, most browsers use specific values.

User Agent Value Comment
Firefox 3.6 and later audio/webm,audio/ogg,audio/wav,audio/*;q=0.9,application/ogg;q=0.7,video/*;q=0.6,*/*;q=0.5 See bug 489071
Safari, Chrome ?  
Internet Explorer 8 or earlier no support for <audio>  
Internet Explorer 9 ?  

Values for scripts

When a script is requested, like via the <script> HTML element, some browsers use specific values.

User Agent Value Comment
Firefox */* See bug 170789
Safari, Chrome */*  
Internet Explorer 8 or earlier */* See IE and the Accept Header (IEInternals' MSDN blog)
Internet Explorer 9 application/javascript, */*;q=0.8 See Fiddler is better with Internet Explorer 9 (IEInternals' MSDN blog)

Values for a CSS stylesheet

When a CSS stylesheet is requested, via the <link rel="stylesheet"> HTML element, most browsers use specific values.

User Agent Value Comment
Firefox 4 text/css,*/*;q=0.1 See bug 170789
Safari 5 text/css,*/*;q=0.1  
Internet Explorer 8 or earlier */* See IE and the Accept Header (IEInternals' MSDN blog)
Internet Explorer 9 text/css See Fiddler is better with Internet Explorer 9 (IEInternals' MSDN blog)
Chrome 12 text/css,*/*;q=0.1  
Opera 11.10 text/html, application/xml;q=0.9, application/xhtml+xml, image/png, image/webp, image/jpeg, image/gif, image/x-xbitmap, */*;q=0.1  
Konqueror 4.6 text/css,*/*;q=0.1  

Document Tags and Contributors

 Contributors to this page: fscholz, teoli
 Last updated by: fscholz,