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Aastha Shaw / August 12, 2022 March 13, 2025

What is a Valid Email Address Format?


What is a Valid Email Address Format

Email marketing is one of the strongest ways to connect with your target audience and convert them. But to run email marketing campaigns, you need ‘valid’ ✅email addresses.

Why do we say ‘Valid’🤔?


Firstly, it is important to ensure that the email address is correct and actually exists so that you know you are reaching out to a real person.

Secondly, invalid email addresses can ruin your database, resulting in hours of wasted efforts and expense.


So let’s dig into what makes a valid email address format and how Clearout can help you validate email address formats.

What is a Valid Email Address Format?


First of all, let’s understand what a valid email address contains:

1. The local part or username – Indicates a unique mailbox name consisting of any combination of letters, numbers, and 7-bit ASCII special characters. In the local part, periods are also acceptable, provided they aren't the first or last character.

2. The symbol – You cannot have an email address without the symbol. It is the connector between the person who owns the email address and the domain.

Including the @ symbol, it allows your email program to recognize the first half of your address as the username and the second half as the domain name.

3. The domain – Each domain occupies a unique place on the web and is controlled by a particular mailbox provider or association.

It consists of one or more parts separated by a dot. Each part must be no longer than 63 characters and can contain any combination of letters and numbers without having a hyphen as the first or last character.

Hence, an email with all of these elements per the guidelines is a valid email address format.

Examples of Valid Email Address Formats:


  • [email protected]

  • [email protected]

  • [email protected]

Examples of Invalid Email Address Formats:


  • @clearout.io – (contains no username)

  • John.doesocialfrontier.com – (contains no @)

  • [email protected] – (contains no domain name)

Now, let’s have a quick look at what invalid email addresses are and their cause.

What is an Invalid Email Address?


An invalid email address refers to an email address that doesn't meet the necessary criteria for proper formatting or functionality and cannot receive emails. They are like zombies: dead but able to eat away your email campaign's life actively.

What makes an email address invalid?


1. Human error– Typos can happen at the point of access by either the person trying to signup or by a company representative when getting the information. Sometimes users intentionally provide incorrect information for exploiting the system for free with multiple signups.

2. Formatting– Email addresses must consist of 4 components: the regional address, @, the domain name, and the domain name identifier. If an email address is missing any of these components, it will be invalid, and there will be no inbox for messages.

3. Domain– There are circumstances when an email address fulfills the format criteria. However, it can still be void if the domain no longer exists. This may happen if a business goes out of business or changes names.

4. Missing mailbox– An email address also becomes invalid when no mailbox is attached to it. This happens when the mailbox is deleted/deactivated by your ESP or if the server is not reachable.

5. Abandonment– When a person switches to a new account with the same or a different email supplier, the original email address commonly gets deserted and becomes invalid due to no engagement.

Knowing what is a bad email address or what makes an email addresses invalid and how they get into your system can help you stop them immediately from hindering your email campaign's performance. This is why validating all email addresses entering your database is essential.

Why Do You Need To Validate Email Addresses?


Invalid email addresses entering your system should not be taken lightly, as there can be severe consequences for sending out email campaigns to invalid emails. Wasted resources, a high bounce rate, a poor ISP rating, and more—you will end up tarnishing your reputation and your brand.

For example, a 10% hard bounce rate in an email marketing campaign causes email provider blockades, resulting in only 44% of emails reaching inboxes. Moreover, fewer emails in the recipient's inbox already affect your results, exacerbated by email provider blockings such as soft and hard bounces.

Therefore, to avoid landing in a lot of hot water by sending emails to invalid email addresses, you need to set up a system to identify, validate, and stop such emails from degrading your database.

How To Validate an Email Address with Clearout?


As mentioned, an invalid email address can cause a host of troubles for your organization. So how do you ensure you avoid falling prey to these scenarios and only collect emails that both exist and benefit your company?

This is where Clearout comes into the picture.

Clearout validates an email syntax and verifies if the email address is real, exists, and is not spammy. Here's how:


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User Picture
(Did you mean : )
Safe To Send
? Based on best practices followed in the industry, Safe To Send flag will provide one of the 4 values to know the deliveriablity chances
Yes - Valid mailbox addresses with guranteed deliveriablity of message thus help to keep sender reputation high %
No - Invalid mailbox addresses can be safely removed, try sending message will bounce and degrade the sender reputation
Risky - Contact these email addresses only when bounce rate is less than 5 % or when using own email sending service
Unknown - Due to unavoidable reasons the status of the email cannot be determined, so retry before using them
Status
? What does Status value means?
Valid - Secure, go ahead and send
Invalid - Don't send, drop these emails
Catch-all - Maybe, at your own risk
Unknown - Don't send, verify later an hour to know the status
Reason
Account
Domain
Disposable
Free Account
Role Account

Real-time verification to keep out invalid entries:


With Clearout’s real-time email verification, you can ensure that you capture only valid email addresses, leading to a clean and reliable database. There are multiple ways– from a custom API to a JavaScript widget – to connect your landing pages, forms, apps, and more to Clearout.

real time email verification to stop invalid email addresses

Bulk verification for maintaining a healthy database:


Moreover, using Clearout's bulk email verification, you can verify millions of emails already existing in your database or CRM. You can connect your tools with an API, native integration, Zapier, Make, etc., or upload your list to Clearout for bulk validation.

bulk verification to remove invalid email addresses

With Clearout, you can be confident in your email campaigns without worrying about bounces and a bad reputation!

Find valid email addresses with Email Finder:


Another way to ensure you get the valid email addresses of B2B prospects is by using the Email Finder.

The Clearout Email Finder lets you search for your prospects' verified email addresses using their name and company or domain name in seconds. You can find email addresses individually using the quick email finder or find more at a time using the bulk email finder. It ultimately helps you build a high-quality list for your cold outreach campaigns.

email finder to find only valid email addresses

Email Validation FAQ


Why am I getting an invalid email address?


Typos are one of the most common reasons for unintentionally getting invalid email addresses into the database. Again, the number of fake signups increasing for abusing the system also contributes to a large number of disposable and invalid emails entering your system.

How do I fix an invalid email address?


The best ways to fix an invalid email address are:

1. Validate email addresses as they are entering your email list and remove the invalid email addresses
2. Look for type errors and fix them
3. Use the double opt-in method to ensure the emails exist and the user is opting-in purposefully

What is the syntax of a valid email address?


The syntax of a valid email address is local-part@domain, where the local part may be up to 64 octets long, and the domain may have a maximum of 255 octets.

What is Email Validation?


Email validation is the process of determining the deliverability and validity of an email address. It entails employing various methods, such as syntax checking, typo checking, SMTP verification, and so on. It makes it simple to detect and eliminate bogus email addresses. As a result, you can keep your mailing list clean by including only valid email addresses.

How do you set up Email Validation?


Email validation can be easily set up using:
Clearout’s API
Integrations
Widget
Plugins
It makes it simple to validate email addresses. All you need to do is an API key, embed it and start validating email addresses.

How do I validate an email address without sending an email?


The extra step to verify an email address before sending out your email campaign will drastically improve deliverability and reduce email bounces and spam complaints. Some ways to validate an email address without sending an email are– email validation tools, email finder tools, using databases like Apollo, Zoominfo, etc.

check for valid email address format with clearout
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