Can I customize number of displayed posts per page

Custom Query String Reloaded plugin will do that.

Or something like this in your archive template:

<?php
$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$args=array(
  'showposts'=>10,
  'paged'=>$paged
   );
global $wp_query;
query_posts(array_merge($args,$wp_query->query)
);
?>

<?php //your loop etc starts here
while (have_posts()) : the_post();
?>

I appreciate the quick response.

I might be being a little dim but I can’t find that plugin?

Comes up as very first item using:
https://www.google.com/search?q=wordpress+plugin+Custom+Query+String+Reloaded

got it now

Many thanks – looks perfect for the job

I have two archive templates one that shows 18 post and the other 5 posts.
My site is setup with 6 parent categories and 1 parent category with 5 sub categories.

The archive template that shows 5 posts will paginate to the second page, but if i could to the third page, it sends me to my 18 post archive template blank. The sub categories however don’t even make it past the first page of pagination. Any clues?

Hope I’ve made myself clear, it’s a bit confusing to sort out.

Never mind, I found a work around. I basically just added the code you provided to my archive template with the 18 posts and change my global posts per page to 5. Thanks.