How long should emails be?

[nighthawk]

How many characters email address have. I usually put VARCHAR(30) in database for storing emails, but is there emails longer than this.

What is optimal length of field in database for email?

[nighthawk]

I found answer to this question 150 - 200 if you want to be safe.

[rse]

I've taken a bit of a scientific approach to this question.

An email address could potentially be split up into at least 4 sections i.e. firstname.surname@domain.com

The longest name I could find in the English language is pneumono­ultra­micro­scopic­silico­volcano­coniosis, which has 45 characters. It is possible that the firstname and surname could be 45 characters long so that would be 90 characters in total. It is then common for a user to separate their names with either an underscore or a hyphen, so that's 91 characters in the first section.

For the domain part, including the @ symbol, a domain name can be upto 64 characters for most registries, although a domain can theoretically be upto 257 characters (inc. @) however this is highly unlikely, so we assume 64.

Next we have the domain suffix i.e. .com/.co.uk etc. The maximum this can be is xxx.xx, so 6 characters.

So if we add it all together we've got 91 + 64 + 6 = 161 characters. I think this figure would be worst case and should allow for all eventualities.

I hope this helps!

[nighthawk]

Thank you, nice work finding the longest word in English language.