Few days ago I was checking my blog’s statistics in the Google Webmaster Tool , while checking across the Html improvement suggestion tab I found that some of my blog’s pages are having duplicate title . On careful examination I found that these are the category and tags pages. Duplicate content can have serious negative impact on your websites search engine ranking . Specially after the recent panda and penguin Google update there are chances that your website could be penalized because of this issue.
When you have good number of posts ( say more than 10 ) under same category or tag , multiple pages get created under these categories or tags. Lets say for a while that you have a category named ‘gadgets’ and there are 20-30 posts under this category. The Category list page shows 10 posts in that category, with “previous” and “next” links to see 10 more.The URL’s are something like below
1st Category page: http://www.mysite.com/category/gadgets
2nd Category page: http://www.mysite.com/category/gadgets/page/2
3rd Category page: http://www.mysite.com/category/gadgets/page/3
The problem here is that WordPress generates same title for each such page, that creates duplicated title tag problem. This is not good from the SEO point of view. You can remove duplicate titles in two ways either by updating the title tags or by making tags and categories noindex, which will prevent it from getting indexed in the search results. You can make them noindex either through robots.txt file or through some WordPress Plugin. I prefer to do it manually by updating the code.
All you have to do is to edit your WordPress blog’s header.php file and look for thise tag </title> and just before </title> put this below code
<?php if ( is_home() ) ?>
<?php if ( $paged < 2 ) {
} else { echo (' | page ');
echo ($paged); } ?>
and then save the file, now all your category and tags pages will have different title. It will be like the below format
title | page 2
title | page 3
This will remove the duplicate titles from all wordpress catogory and tags pages.