[codyrobbins]

Using or not using a regex to validate email addresses misses the point. You should simply be delegating this task to the library that you’re using to send mail in the first place. If the mail library can’t deal with a particular address, then it’s not worth accepting because you’re not going to be able to send anything to it anyways.

If you have a Rails app you’re most likely using the Mail gem to send mail, so that’s why I wrote this: https://github.com/codyrobbins/active-model-email-validator. It lets the gem worry about whether an address is valid. Since the mail library is actively maintained, in my opinion it’s a safe bet to trust that it is properly parsing and validating addresses insofar as is possible.