You may wish to Show a limited number of posts on home page but more Posts On category,tag,archive and Search results pages.This WordPress plugin will do this for you.
The Custom Query String WordPress plugin lets you completely customize how many Posts Appear in Different pages of your Blog.Using this you can set Conditions as per your desire.
The Interface is very Simple as shown below
Just add the Rules that You need and Voila ! plugin you can also choose the number of posts on Individual Category pages.
Another Simpler Setting :Consider a Situation when you wish to Show 5 Posts on your Blog’s Homepage but more posts (say 10 posts) on all other pages(category,tag,search,archive etc) of your Blog.
1.From your WordPress Admin panel Go to the reader Settings.Under the field “Blog Pages show at most” set the Number of posts you wish to see on All other pages
2.Now From Settings go to “CQS” ( Custom Query String ) and Set the Homepage rule to 5.
That’s it.Now Your Homepage will show 5 posts while all other pages will show 10 posts.Thanks Daily Blog Tips