How to validate an email address in Go

Question

The standard lib has email parsing and validation built in, simply use: mail.ParseAddress().

A simple “is-valid” test:

func valid(email string) bool {
    _, err := mail.ParseAddress(email)
    return err == nil
}

Testing it:

for _, email := range []string{
    "good@exmaple.com",
    "bad-example",
} {
    fmt.Printf("%18s valid: %t\n", email, valid(email))
}

Which outputs (try it on the Go Playground):

  good@exmaple.com valid: true
       bad-example valid: false

NOTE:

The net/mail package implements and follows the RFC 5322 specification (and extension by RFC 6532). This means a seemingly bad email address like bad-example@t is accepted and parsed by the package because it’s valid according to the spec. t may be a valid local domain name, it does not necessarily have to be a public domain. net/mail does not check if the domain part of the address is a public domain, nor that it is an existing, reachable public domain.

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