#normalize-email

This package is intended to help reduce multiple sign-ups using the same mail-address by applying general and provider specific rules to email addresses, thereby transforming them into a standardised form.

With this John.Doe+marketing@GoogleMail.com becomes johndoe@gmail.com. As these addresses are both for the same mail account, there is risk in this method. The following transformations can be applied based on the address' domain:

• Remove characters (for example the . in Gmail-Addresses)
• Remove subaddresses (usually the part after the +)
• Rewrite domains (googlemail.com → gmail.com)
• make localpart and domain lowercase (JohnDoe@… → johndoe@…)

#Missing rules

If you know about more rules, please open an issue or send it via email

#Important notes

Do not send mails to the normalised addresses! Always use the user-provided address as things like subaddresses and receiver-side sieves can affect deliverability. Just because joe+site@gmail.com and joe@gmail.com belong to the same account, does not mean that they are equal.

This library can not detect server side settings. If the subaddress delimiter is set to -, this library will still assume it's +. There is simply no way to do that. This may – though highly unlikely – lead to non-functional addresses being produced. The low likelyhood of this happening to two users on the same domain with the same odd address (joe+doe@… and joe+deere@…) makes this something considered acceptably rare. Again: do not send mails to normalised addresses!

#Stable version

This library is considered stable and considered feature-complete. The only planned updates are updating or adding rules. To avoid creating a new tag at every commit, no tags will be added to this repository and origin/HEAD should be considered stable.