Whats the definitive maximum size of an email address?

shawson — Tue, 01 Dec 2009 09:41:12 +0000

I’ve written lots of app’s which store email addresses, and usually go for a nvarchar(100) to store them, but thought I would find out once and for all, what the actual maximum size was- just out of curiousity.

Having googled around, I came across a couple of lengthy posts on the matter (here and here), quoting figures from various standard (which seemed to point at 320 character), then corrections to those standards by members of ICANN based on the SMTP spec and so on and so forth…

After much trawling, it seems the official answer is : 254 characters (256 including the standard <> brackets around the address)

Premailer — preflight for HTML e-mail

shawson — Thu, 27 Aug 2009 10:41:46 +0000

Stumbled across a handy on-line tool for processing html used in email’s- which is notoriously picky. This tool converts all your css declarations to be inline as well as update all your links and image paths to be absolute- not masses but saves you picking through and doing it manually.

Premailer — preflight for HTML e-mail — dunae.ca.

There’s another site up which guides you through standards which should help you get the best results from your email across all the main email clients ; www.email-standards.org

Shawson's Code Blog » Email

Whats the definitive maximum size of an email address?

Premailer — preflight for HTML e-mail