You already know Google Pagespeed, a pack of tools and services for optimizing the performance of websites.

And, they have a widely-used module named mod_pagespeed that auto-applies the best performance practices to Apache-hosted websites.

There is now a Windows alternative for it, IISpeed, that is free and offers the same feature set.

IISpeed - Google Pagespeed For Windows

It is capable of minifying, rewriting and combining JavaScript + CSS files, optimizing + auto-spriting images and many other stuff provided by Pagespeed.

IISpeed is installed on the server level and it is compatible with IIS 7,7.5 and 8.

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