What is the proper minimum length of an email address as defined by the IETF or the like?

Question

I am specifically looking for the minimum length of the prefix and domain. I've seen conflicting information and nothing that looks authoritative. For reference, I found this page which claims that a one character email address is functional:

http://www.cjvandyk.com/blog/Lists/Posts/Post.aspx?ID=176

and I tried validating email addresses at gmail and they expect prefix greater than or equal to 6. These are obviously way off. My web framework expects prefix greater than or equal to 2.

What gives?

Thanks, David

Answer 1

The shortest valid email address may consist of only two parts: name and domain.

name@domain

Since both the name and domain may have the length of 1 character, the minimal total length resolves to 3 characters.

Answer 2

I believe the standard you are looking for is RFC 2822 - Internet Message Format

More specific infor on email address restrictions on RFC 3696 - Section 3

I originally got this info from Phil Haack's blog post.

Answer 3

The shortest domain name is four characters, so an email address is at least six characters.