Apache RewriteRule Flags

12 March 2022

What does common flags like [NC], [QSA], [F], [G] [L] means?

Flag	Description
[NC]	Use of the [NC] flag causes the RewriteRule to be matched in a case-insensitive manner.
[QSA]	When the replacement URI contains a query string the default behavior of RewriteRule is to discard the existing query string and replace it with the newly generated one. Using the [QSA] flag causes the query strings to be combined.
[F]	Using the [F] flag causes the server to return a 403 Forbidden status code to the client.
[G]	The [G] flag forces the server to return a 410 Gone status with the response.
[L]	The [L] flag causes mod_rewrite to stop processing the rule set. In most contexts this means that if the rule matches no further rules will be processed.

Examples

RewriteRule ^test$ /some.php [NC]

Rule above will accept both URIs /test and /TESt, case is ignored by NC flag.

RewriteRule ^test$ /some.php?q=2 [QSA]

Rule above will rewrite /test to some.php?q=2 and it will also pass any additional query parameter. For example:

/test?extra=1 will be rewritten as /some.php?q=2&extra=1