AdSense and WordPress 404s

If you're using AdSense in your sidebar or header (two relatively popular spots in WordPress templates) you need to be aware that Google prohibits the placement of AdSense blocks on Error pages. If you're using a custom 404 page this can pose a problem. The trick here, of course, is that you want to make sure you keep your ads on every other page - but you don't want them appearing on your 404 pages.

Luckily WordPress has a series of "Conditional Tags" that can help you overcome this dilemma.

Feel free to browse through some of the tags before continuing here... they can be helpful in a number of different ways (many of which I'll discuss eventually). For our purposes here though, we're particularly interested in the "is_404()" function.

Basically, the "is_404()" function asks the WordPress engine if the page being loaded is the 404 Error page. If it is, then the function returns "true;" if it's not then the 404 Error page then the function returns "false."

Mix this with some PHP and we can setup a PHP conditional statement that will do the job.

<?php if (!is_404() ) { ?>
AdSense code goes here.
<?php } ?>


This block is quick and simple - it just tells the server to show the AdSense code only if the page is not using a 404. If you're using more than one company for advertising, and the second company allows ads on 404 pages, you can take it a step farther.

<?php if ( !( is_404() ) ) { >
AdSense code goes here
<?php } else { ?>
Code from other company
< } ?>


With this code you can keep the template profitable while still abiding by AdSense's TOS.