What Is a Valid Email Address Format?

By Bulk Mail Verifier | 11/3/2023, 8:13:44 PM

When you want to use any email platform, you need a valid email address to use that platform. Without that, it would be invalid. Now you must be thinking about the question here that: what are the factors that show the email address is valid? Generally, a compelling valid email address characters consist of an email prefix and valid email domains, both in acceptable formats. The prefix appears to the left of the @ symbol, and the domain appears to the right of the @ symbol. Without this, email domains are not valid.

For example, in the address example@mail.com, "example" is the email prefix, and "mail.com" is the email domain.

In both parts, there are some specifications mentioned online that determine what characters are acceptable for them. Their specifications are called Requests for Comments (RFC), published by the Internet Engineering Task Force (IETF) and the Internet Society (ISOC), the principal technical development and standards-setting bodies for the Internet. There are a lot of free unlimited email verifier online services that provide email verification services so that your email marketing campaigns can continue.


The maximum upper limit of characters for a prefix is up to 64 in length. It can be a combination of any alphabetic characters, numeric values or any of the special characters mentioned below,

# ! % $ ‘ & + * – / = ? ^ _`. { | } ~

The period character (".") is valid for the prefix part with the following restrictions:

  • It is not the first or last character
  • Two or more than two consecutive periods


The Domain name is a series of letters and digits that explains a space on the Internet possessed and controlled by a particular mailbox provider or association. Each domain is unique and occupies its special place on the World Wide Web. These domains contain an effective internet email address format with valid email characters. No two domains have the exact domain name. The Domain part cannot exceed the upper limit, which stands at a total of 255 characters in length and should conform to the specification for hostnames, which is a list of dot-separated DNS labels. Each DNS mark must not surpass 63 characters and should comprise of any blend of alphabetic characters, hyphens, and digits. Some of the restrictions apply to the DNS labels,
• The first and last characters cannot be hyphens.
• Top-level domains cannot be all numeric.


Amongst several other questions that are on one's mind, the most common one would be: "is the email valid?" There are some tricks to know that the email address is valid or is invalid. If a person tells you the wrong email address, then there is a way to check the email address with the help of this simple trick, whether the email exists or not. Many different methods are available to correct this, but with the help of this easiest trick, you can check the validity of an email address in just seconds. All you can do is, open the login page of your email service provider and then click on the forgot password button. You can just enter the address; then, the message will appear whether the email is valid or not.

Some valid email address examples with valid email address formats are:

  • michaelj@domainsample.com
  •  j@domainsample.net
  •  j43@domainsample.co.uk

The IDs shown above also include valid characters in email addresses, which are used in a valid address format.

Some of the examples of the invalid email addresses and their faults are:

  •  @domainsample.com, the reason is, that the recipient's name is missing.
  •  Com, the reason is, that a symbol of @ is missing between johndoe and domainsample.com
  •  com; the reason is, that the domain name is missing after the @ symbol and before the top-level domain (.net).
  •  doe43@domainsample, the reason is, that the top-level domain (.co.uk) is missing.

If you are running a marketing campaign sending out emails to invalid email addresses. It cannot be something that should be taken lightly, as it can have severe repercussions. At the very least, your campaign will not be effective, and you will be wasting precious resources by sending emails to addresses that are not there. The consequences can be much worse than this; however, if you are not careful, you can end up in a lot of hot water by sending out those emails to invalid email addresses.