IISpeed – Google Pagespeed For Windows Servers
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 is installed on the server level and it is compatible with IIS 7,7.5 and 8.