I’ve discovered that Gmail treats certain email addresses as the same even when they look different. For example, [email protected] and [email protected] both deliver to the same inbox. This is causing issues in my application because I need to group these duplicate addresses together.
I want to create a function that can standardize these Gmail addresses so they all look the same in my database. Does anyone know what the exact rules are for Gmail address normalization? I need to understand all the different ways Gmail considers addresses to be equivalent so I can write proper code to handle this.
Basically, if someone registers with both versions of their email, I want to treat them as the same user account instead of creating duplicates.
To normalize Gmail addresses, remember that Gmail ignores dots in the username section, meaning [email protected] and [email protected] are considered the same. Additionally, any characters after a plus sign are not taken into account, so [email protected] will also route to [email protected]. You should implement a function that removes dots and disregards any plus sign and following characters when storing these emails in your database. This approach keeps your user records clean without altering the original email addresses.
Gmail normalization involves two primary rules: dots in the username are ignored, and email addresses are case insensitive. This means that [email protected] and [email protected] are equivalent. To effectively manage this in your application, convert all addresses to lowercase, remove periods before the ‘@’ symbol, and disregard any characters after a plus sign. However, be cautious as these normalizations only apply to gmail.com and googlemail.com domains; other email providers may treat dots differently. It’s wise to retain both the original and normalized addresses for reference.