STRING, read-only.

Available in all subroutines.

The file extension specified in a URL.

If multiple file extensions are present, only the last extension is used. For example, given the path /, req.url.ext would be txt. If no file extension is present, the value will be an empty string.

This variable is updated any time req.url is set.


In the request, req.url.ext will contain html.

Try it out

req.url.ext is used in the following solution recipes, which show real world use cases. Click RUN to provision a Fastly service, execute the code on Fastly, and see how the function behaves.

Image transformation classes

Use custom, predefined classnames like large, medium, small, teaser, thumb, or article to control Fastly Image Optimizer and optionally prevent end-user access to native properties like 'width'.

User contributed notes

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