Which is better for SEO ?
Webmasters Stack Exchange is a question and answer site for webmasters. It only takes a minute to sign up.Sign up to join this community
Case sensitivity doesn't matter for SEO. HTML, when used properly, does offer search engines clues about the content of a page but whether those tags and their attributes are capitalized or not is irrelevant. (Although it may matter for validating your HTML depending on the Doctype you choose).