What is the actual minimum length of an email address as defined by the IETF?

validation email email-validation
David Watson picture David Watson · Sep 14, 2009 · Viewed 58.8k times · Source

I'm 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

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.

Answer

user151323 picture user151323 · Sep 14, 2009

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.

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