Regex for email but that can include whitespaces

Question

I have a regex question, there is field for email of 60 characters. I got the regex working for email validation, but I am not sure how to ignore whitespaces after the email but only upto the whole string is 60 chars. If there is anything after 60 chars then its not valid.

^([A-Za-z0-9!#$%&'*+/=?^_`{|}~-])([A-Za-z0-9.!#$%&'*+/=?^_`{|}~-])*[@]([A-Za-z0-9.\-])([A-Za-z0-9.\-])*[.][A-Za-z.]{2,6}[ \t]+$

This should be a valid string (I am using quotes here to show string length) 'test1.test123@testtesttest.com '

This should not be a valid string 'test1.test123@testtesttest.com m'

The premise sounds a bit odd. Why would you limit the length to 60 characters *with* whitespace? I think it'd make more sense to remove the whitespace before saving it or whatever, because it does no good. Also why such a short limit? It's 2018, we have disk space. — Matti Virkkunen, May 01 '18 at 08:17
[Trim](https://msdn.microsoft.com/en-us/library/t97s7bs3(v=vs.110).aspx) the string before testing it? — Matt Raines, May 01 '18 at 08:17
You're probably going to trim the string anyway. I would trim it and compare the length of both before and after. — 41686d6564 stands w. Palestine, May 01 '18 at 08:22
Trying to do this with one regexp is probably going to end up being pretty ugly. Regex isn't really made for this. — Matti Virkkunen, May 01 '18 at 08:30
Try validating the length with and `if` statement then remove the spaces and validate using normal email regex — Mohammad Ali, May 01 '18 at 08:53
I am looking for a regex solution. Could have done in code but that is not an option I have. — mehwish, May 01 '18 at 08:59
Why do you need to do it solely in regex if you dont mind me asking? — TheGeneral, May 01 '18 at 09:09

user1672994 · Answer 1 · 2018-05-01T10:22:39.647

The mentioned regex does not work (see below)

So I've used mine and added validation for max limit of 60 chars

^(?!^.{60})(([\w-]+\.)+[\w-]+|([a-zA-Z]{1}|[\w-]{2,}))@((([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\.([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\.([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\.([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])){1}|([a-zA-Z0-9]+[\w-]*\.)+[a-zA-Z]{1}[a-zA-Z0-9-]{1,23})

This regex uses lookarounds syntax. You can see the output in various screenshots. You can check how it works at here.

Here (?!^.{60}) matches max limit of 60 chars. And rest of regex syntax to validate the proper email address.

If also, see that the regex does not validate the string test1.test123@testtesttest.com m.

Thank you for your efforts, this solution did not achieve all the requirements. — mehwish, May 01 '18 at 10:39

score 0 · Accepted Answer · answered May 01 '18 at 10:18

Well, if you insist on using Regex, you can use positive lookahead to limit the total length of the string by simply adding the following right before your regex:

(?=.{6,60}$)

That would restrict the total length of the input string to be between 6 (the minimum length of a valid email address) and 60 (your preferred maximum length).

You could also replace [ \t]+ with \s+ to match other whitespace characters or with \s* to accept the input if it does or does not end with whitespace characters if you're interested in matching all kinds whitespace characters.

Therefore, your pattern would look something like this:

^(?=.{6,60}$)([A-Za-z0-9!#$%&'*+/=?^_`{|}~-])([A-Za-z0-9.!#$%&'*+/=?^_`{|}~-])*[@]([A-Za-z0-9.\-])([A-Za-z0-9.\-])*[.][A-Za-z.]{2,6}\s*$

Try it online.

Hope that helps.

Glad I was able to help. – 41686d6564 stands w. Palestine May 01 '18 at 12:44 — 41686d6564 stands w. Palestine, May 01 '18 at 12:44

Regex for email but that can include whitespaces

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