The Meta keywords should not contain more than 255 characters
. Novice webmasters will attempt to spam the Meta keywords with huge list of keywords which they hope their site will rank for. If your site is already popular, spamming the Meta keywords with a lot of keywords won't hurt your ranking. If your site is new, using a lot of keywords in the Meta keywords will cause you to rank lower. Each keyword in the Meta keyword field must be separated by a comma. The purpose of the Meta keyword tag is to help the search engine find the focus topic of the page.