ISAPI_Rewrite is a powerful regular-expressions-based URL manipulation module for IIS. It is compatible with Apache mod_rewrite syntax, which makes it possible to move configurations from Apache to IIS and vice versa just by copying .htaccess files. Please see this compatibility chart.

Top features of ISAPI_Rewrite:

  • ISAPI_Rewrite offers the same syntax and behavior as Apache mod_rewrite making it possible to migrate configurations just by copying .htaccess files. Read more about mod_rewrite compatibility here.
  • Regular expressions for flexible and powerful configurations.
  • Extremely fast and highly scalable pure C++ code.
  • Real distributed configurations: global (server) level, virtual host (web site) level, directory level .htaccess files with real-time monitoring.
  • Isolation – user level configuration affects only local user environment making ISAPI_Rewrite ideal solution for web hosting providers.

Top usage examples:

  • Search engine optimization. Read more.
  • Proxy content of one web server through another web server. Read more.
  • Prevent content leeching (direct linking). See example.
  • Block specific hosts, referrers or annoying robots.
  • Content negotiation - serving different files for different languages or different browsers. See example.
  • Emulate load balancing for web cluster. See example.

Please find more useful examples in ISAPI_Rewrite documentation here and in Apache documentation here. Most Apache examples can run with ISAPI_Rewrite without modification.

Pricing details

  • Free 45-day trial period.
  • Single server (computer) license - $99.
  • ISAPI_Rewrite Lite version is Freeware! (Read on specific limitations).
  • Volume discounts available!