Brian Dunning's FileMaker Custom Functions

IsValidEmail ( theEmail )

Determines if a supplied email address is valid or not

  Average rating: 3.6 (68 votes) Log in to vote

Paul Turnbull   Paul Turnbull - Show more from this author
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  Sample input:
IsValidEmail ( "" )
  Sample output:

  Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

Takes a text string a checks to see if it is a valid email address. Includes a value list of over 260 Top Level Domains that are checked against. If the string is not a valid address it returns an explanation of the why the test failed.

Will not handle urls in the form "" although you could edit to handle this if you like.

Edited 11/13/05 - fixed bugs.



Benka   Benka, Rennes, France
Jun 3, 2009
Hello Paul,

Thank you for the function.

Little bug :

ééééé return true

text return true return true
Benka   Benka, Rennes, France
Jun 3, 2009
text return true
Jamie Thompson, Computech IT Services Ltd.   Jamie Thompson, Computech IT Services Ltd., Plymouth, UK
Mar 10, 2011
Great function. However, he ampersand (&) is a valid character in an email address.
Marc   Marc, San Diego, CA
Mar 11, 2011
Naming the function "IsValidEmail" in FileMaker 11 conflicts with an internal existing function name.

Maybe rename to "IsThisValidEmail"?
Anyway, thank you and I like this function very much.
Dennis   Dennis, JC Raulston Arboretum
Aug 24, 2020
According to RFC2696 ( the local-part of an email can contain several of the characters that the code above declares invalid. To quote from the RFC:
"Without quotes, local-parts may consist of any combination of
alphabetic characters, digits, or any of the special characters

! # $ % & ' * + - / = ? ^ _ ` . { | } ~

period (".") may also appear, but may not be used to start or end the
local part, nor may two or more consecutive periods appear. Stated
differently, any ASCII graphic (printing) character other than the
at-sign ("@"), backslash, double quote, comma, or square brackets may
appear without quoting. If any of that list of excluded characters
are to appear, they must be quoted."

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