A valid email is of the format: [email protected] The name can be a set of ‘atoms’ separated by dots. single or double quotes and any character inside the quotes Now, to the domain part. MUSEUM .travel, .international or even .vermögensberatung For example all the following email addresses are valid: Source The sad truth is that despite the complex regular expression validation, the email may not be existing, so can still be invalid for practical purposes.In its simplest form like this: [email protected], the atoms can contain 1. Most email validation checks assumes that the top level domain can have up to 4 characters. You have just validated the format – not its existence.However, you should always secure your application with open source high caliber sanitization code on the server.I know this is old, but this can be simplified to: return String(e).match(/^\s*[\w\-\ _] (? :\.[\w\-\ _] )*\s*$/); It will return null if no match and a single item array of the email address itself if it does match.