The .htaccess is one of the most important and busiest file on your web server since it is accessed and consulted on any HTTP request.

The .htaccess tester is online tool that will help you check the various rewrite rules that are part of your .htaccess file.

You can also specify a custom Referral URL to emulate incoming requests to your web server from other servers. Always do a test before pushing any mod_rewrite rule to the server.