Are Email Addresses Case Sensitive? Quick Experiment.
I recently came across this thread on StackOverflow which talks about whether email addresses are case sensitive or not.
Let’s say you send an email to the addresses: firstname.lastname@example.org, Contact@example.com and CONTACT@EXAMPLE.COM. As you can see, all three emails have the same spelling, but the first is all lowercase and the other two are a mixture of both upper and lowercase. So what happens when you send an email to all three? Are they all in one inbox or in another? Or in other words, are email addresses case sensitive?
The short answer is no. In most cases, email addresses are not case sensitive. All three will arrive at the same mailbox, that is, email@example.com.
Long answer, it depends. There are two parts to this question, the username before @ and the domain name after it.
The domain name (for example, @ gmail.com or @ free-online-converters.com) is not case sensitive, so example.com is the same as EXAMPLE.COM.
Now we are left with the part of the username (the one that comes before the @). Technically, it is up to the host or email providers to decide whether they want to keep the username case-sensitive or not.
Most major email providers like Gmail, Outlook and even corporate email addresses hosted by Google Suite are not case sensitive. Just to avoid unnecessary confusion. However, in extreme cases, some large companies apply case sensitivity on their servers, as some people may often have the same first and last name. But in general, this creates more confusion than usability, which is why most standard email providers avoid case sensitivity.
To test this theory, I ran a quick experiment.
Since we are already using firstname.lastname@example.org, I tried to create another email account with the first uppercase letter, which is Contact@pkrtousd.gb.net And I immediately got an error saying the username is not available. I have the same error on Gmail, Apple ID, Outlook, ProtonMail, which, according to most online sources, account for over 90% of total email volume by market share.
In short, while it is technically possible to make the pre @ part case sensitive, most popular mail servers do not allow this.
It’s safe to assume that your message will be delivered to the same email address regardless of upper or lower case as long as the username is spelled correctly.