Optimal Length for Search Engines. Google typically displays the first 50-60 characters of a title tag, or as many characters as will fit into a 512-pixel display. If you keep your titles under 55 characters, you can expect at least 95% of your titles to display properly.
Meta descriptions can be any length, but search engines generally truncate snippets longer than 160 characters. It is best to keep meta descriptions between 150 and 160 characters.