Using Permalinks

Permalinks are the permanent URLs to your individual weblog posts, as well as categories and other lists of weblog postings. A permalink is what another weblogger will use to link to your article (or section), or how you might send a link to your story in an e-mail message. The URL to each post should be permanent, and never change — hence permalink.

Permalink Types

There are three basic types of WordPress permalinks:

1. Default: “Ugly”
   The default links, which looks like this:
   http://example.com/?p=N
   where N is the Post ID number. It works on all server environments, but it doesn’t look as nice as some of the other options.

2. mod_rewrite: “Pretty Permalinks”
   Using mod_rewrite or lighttpd you can produce much nicer permalinks (see Pretty Permalinks). There are many different formats, but the most common, and most versatile looks like:
   http://example.com/category/post-name/
   or http://example.com/year/month/day/post-name
   Some people eliminate some or all of the date elements (day, month, year) to have a shorter permalink format.
   Pretty permalinks are available under:
   Apache web server with the mod_rewrite module
   Microsoft IIS 7+ web server with the URL Rewrite 1.1+ module and PHP 5 running as FastCGI
   Microsoft IIS 6+ using ASAPI_Rewrite
   Lighttpd using a 404 handler or mod_rewrite (see See Also)

3. PATHINFO: “Almost Pretty”
   PATHINFO permalinks look very much like mod_rewrite permalinks but for one exception: they have /index.php inserted before them, like so:
   http://example.com/index.php/yyyy/mm/dd/post-name/
   Otherwise, they are the same as the “pretty” mod_rewrite permalinks, and are similarly flexible. Anything that mod_rewrite permalinks can do, PATHINFO permalinks can do, with the help of that /index.php part. There is a helpful plugin that displays the type of permalinks being used and detailed information on the internal rewrite rules used by WordPress.

Choosing your permalink structure

In the Settings > Permalinks panel (Options > Permalinks before WordPress 2.5), you can choose one of the “common” structures or enter your own in the “Custom structure” field using the structure tags.
Please note: You never, ever put your site url in the permalinks slot. You must use one of the structure tags,
or a combination of tags only.

%year% – The year of the post, four digits, for example 2004
%monthnum% – Month of the year, for example 05
%day% – Day of the month, for example 28
%hour% – Hour of the day, for example 15
%minute% – Minute of the hour, for example 43
%second% – Second of the minute, for example 33
%postname% – A sanitized version of the title of the post (post slug field on Edit Post/Page panel).
So “This Is A Great Post!” becomes this-is-a-great-post in the URI (see Using only %postname%).
Starting Permalinks with %postname% is not recommended, for performance reasons.
%post_id% – The unique ID # of the post, for example 423
%category% – A sanitized version of the category name (category slug field on New/Edit Category panel). Nested sub-categories appear as nested directories in the URI. Starting Permalinks with %category% is strongly not recommended for performance reasons.
%tag% – A sanitized version of the tag name (tag slug field on New/Edit Tag panel). Starting Permalinks with %tag% is strongly not recommended for performance reasons
%author% – A sanitized version of the author name. Starting Permalinks with %author% is strongly not recommended for performance reasons

Using “Pretty” permalinks (IIS)

Permalinks without mod_rewrite

“Pretty” permalinks usually require mod_rewrite, and IIS (common on Windows servers) does not support mod_rewrite. (If you are using Apache 2.0.54, on Windows, mod_rewrite may work, provided it is enabled in apache\conf\httpd.conf.) If you are using IIS 7 and have admin rights on your server, you can use Microsoft’s URL Rewrite Module instead. Though not completely compatible with mod_rewrite, it does support WordPress’s pretty permalinks. Once installed, open the web.config file in the WordPress folder and add the following rule to the system.webServer element

<rewrite>
    <rules>
        <rule name="Main Rule" stopProcessing="true">
            <match url=".*" />
            <conditions logicalGrouping="MatchAll">
                <add input="{REQUEST_FILENAME}" matchType="IsFile" negate="true" />
                <add input="{REQUEST_FILENAME}" matchType="IsDirectory" negate="true" />
            </conditions>
            <action type="Rewrite" url="index.php/{R:0}" />
        </rule>
    </rules>
</rewrite>

Download info and files…

There’s a full installation guide on the IIS site. You can also download a copy of this page, a copy of the Microsoft page, and the required files (for either x86 or x64) from me, here.