Normalizing email addresses

We use email addresses as unique user identifiers, so we’d like to normalize them, mostly to keep users from confusing themselves or their co-workers. Since we can’t normalize the address that users enter before it is passed to Auth0, what normalization does Auth0 perform?

Presumably the domain part is lower-cased, as it’s case-insensitive. Usually, the part before the @ is lower-cased as well, though the RFC allows it to be case-sensitive. More importantly, there can be comments following a plus sign (or using parentheses?), and Google email addresses canonically remove dots.

That is, I’m most concerned with the guy who uses both and and doesn’t realize he’s using two addresses, because they wind up in the same inbox.

1 Like

Hi @DougNChannel I think @jmangelo explains the email case insensitivity quite clearly in his response here Creating a user converts email to lowercase Let us know if that helps.

@ashish The explanation is pretty clear, one thing I’d like to clarify is that if an email provider applies case sensitivity, we will now be unable to reach a user with uppercase characters in the local part of their address. Did you guys consider this case? Did you ever hear of this leading to problems?


hello I want to know what is normazlising an email?

Here’s what normalizing an email is: