This plugin adds a new permalink tag %hashed_id% which represents the encrypted

palicao

This plugin adds a new permalink tag %hashed_id% which represents the encrypted 
version of your post ID. 
Uses hashids library (see http://www.hashids.org/php/).
With this plugin you can change your permalink structure into something like
<pre><code>/%hashed_id%/ 
</code></pre>
to obtain links like
<pre><code>http://www.example.com/B7j1rPk8
</code></pre>
or into something like
<pre><code>/%year%/%monthnum%/%hashed_id%/
</code></pre>
to obtain URLs like
<pre><code>http://www.example.com/2012/10/B7j1rPk8
</code></pre>
or
<pre><code>/%hashed_id%/%postname%/
</code></pre>
to obtain
<pre><code>http://www.example.com/B7j1rPk8/my-slug
</code></pre>
This plugin is useful when you want to obfuscate the number of posts or simply 
if you want an unusual and concise url schema. This is also useful if you want to have 
short URLs without using a third-party service.

Alternatives to WP Hashed IDs

Top alternatives