This is my situation : mydomain.com/abcd mydomain.com/abcd/ Both are indexed in google, it lead to duplicacy of more than 25 pages (5 1000+ word articles) which i wrote myself. This is due difference in permalink and me manually indexing using GWT. I added additional slash in WP permalink whereas my GWT submission was without last slash. I heard that canonical tag will solve this one. i have disabled automatic redirect from .abcd to .abcd/ in WP from theme functions. Now the only thing which i don't know about is this canonical tag. Can someone tell me how to do it. My main question is where to add in the post + which url should be having in canonical tag, the one i want to keep or the one i want to leave. seriously no idea. Google front page content confuses me. i just need answer to above 2 questions. Please understand one thing i have made post for .abcd not .abcd/ . It is due to me doing submission in GWT using .abcd/ . im fucked up. Please take small effort to explain i may come to some help to you in future.