Trademark Search Tool

Although not required prior to filing an application, you are encouraged to search the USPTO's trademark database to see if any mark has already been registered or applied for that is similar to your mark and used on related products or for related services. If your search yields a mark that you think might conflict with your mark, you should then check status to see if the application or registration is still "live," since any "dead" mark cannot be used to block a new application.

You can access the trademark search tool here: Trademark Search Tool

A complete search is one that will uncover all similar marks, not just those that are identical. In this regard, searching for trademark availability is not the same as searching to register a domain name. A domain name search may focus on exact or "dead on" hits, with no consideration given to similar names or use with related products and services. Basically, a domain address is either available or it is not.