The truth is search engines do not even use the keyword Meta tag. They haven’t used it for many years. But in fact many SEO specialists, and most website designers, still may charge a premium for setting this Meta tag.
Google, Bing and Yahoo, the big three do not use the keyword meta tag. Some smaller engines that are meta tag based may, however considering the percentage of the search engine referrals such engines control (less than a few percent total) the Keyword meta tag is essentially irrelevant when it comes to getting visitors to your website.