Email Checker


All you wanted to know about email checkers: definition and principle of work

For everyone working with emails, it is vital to stick to the core issue: deliverability. If you send letters on emails, which bounce them right away or do not accept because they don’t exist, it makes a problem for every sender (especially, for enterprises that have a business model of email marketing in their heart). Also, there may be no human behind this or that email to read it, or an address is fake or just a one-time… With so many reasons for a possible fault of delivering your electronic message to potential readers, you definitely have to use some email validator. So, how to check if an email is valid? There is a guide on email verification specifically for you.


What is an email checker?

Let’s not dive into too tech stuff about email verification process and essence, trying to make our material understandable to a wide circle of readers. So, an email checker is a tool, which is designed to check if some email is okay or not okay. What is included in ‘okay’:

  • If the electronic address exists 

  • If the domain (mail server) is ready to cooperate during checks, it is able to tell that it specifically has such address, it rejects letters sent to this domain on an un-existing e-address, what kind of domain it is (blacklisted or not, a regularly working host or some dummy one used to make spam sends (email spam test) or to register one-day e-addresses). If a server does not want to cooperate during the check, it is impossible to confirm whether any address exists on it

  • If the address is not blacklisted, spammy, fake, one-day, and has a history of using it

  • If the address accepts all or not (“accept all” type of address means that any letter sent to a server to any address is accepted and never returned, even if it does not exist)

  • If this address has appeared anywhere on the Internet as belonging to someone – like it is used in social media, for instance.

Bear in mind that the list above is what ideally can be included in checks but it will super heavily depend on a specific email checker.


How email checker works?

To make sure that some email is okay or not, an email checker connects to the mail domain and exchanges with it a sequence of commands, defining everything that is told above on the list. After that, it makes the Internet search to collect additional information. Based on all data collected, it defines the goodness or badness of the submitted address, marking it okay or not. Depending on the specific email checker you’re using to verify email, the name for the check may differ – for instance, ‘Valid’, ‘Ok’, ‘Passed’, ‘Existing’ and akin…

What the validity of the checked email means? If it is valid, then with the probability of 95% or higher, your email sent to this address will not be bounced. Thus, you are cleaning your database, sending letters to only those recipients, who are highly likely to read the received letter.

Also, it is important to mention that no email address owner of a checked email will know that his or her email was checked, as email checkers do not send anything on the address itself to check if the email is valid. Also, they do not store the database of checked e-addresses (at least, longer than it is needed to make check and form a report), so owners of those e-addresses will not be confused by finding their emails in someplace online. Nobody will know that you did the check. 

In addition – based on the type of subscription you’re having in this checking tool, there are different opportunities to make checks, from a few checks per 1 hour, to several dozen or hundreds per month, and to millions per day in a batch check. There are free and fee-based subscriptions, where most expensive ones can cost ten or more thousand dollars per 1 huge batch check (and the least expensive are something like a few dollars a month). 

Who could find an email checker useful?

There are entire industries who will find email address verification useful:

  1. Marketing companies 

  2. Professional senders of huge amounts of e-letters (and yes, that include spammers, too, sadly)

  3. Any company or private individual who is engaged in email marketing and sends any information to existing or potential clients 

  4. Commercial and non-profit organizations, which want to attract new clients or to have better engagement of existing ones

  5. IT specialists searching for clients or offering anything through the Web.


What about API for developers?

It is often the case that an email tester offers API. With it, developers of various IT companies are able to smoothly integrate with the functionality of a checker, so users of their IT software would use their software with the built-in functionality of email check without the need to go elsewhere to perform this operation. Such integration increases the value of software and brings more clients to developers of email checking tools. 

With API, it becomes possible to make batch checks with ease. If it is present in this or that company, it is done using different coding languages (like Curl, Go, JavaScript, and Python) and is normally represented as the piece of code with instructions on what to do with it., for instance, has a very extensively elaborated API with nice supporting documentation, so it’s a real pleasure for third-party developers to integrate with this email address checker.


What are the benefits of using an email checker?

Such benefits of using email validation optionality are normally considered:

  • Decreasing the bounce rate in your email campaign to 0%... 10%

  • Not wasting your company’s resources to send letters to bad addresses (time, money, efforts)

  • Gaining a bigger assuredness that your emails will be read and responded

  • Keeping your clientele’s addresses database up to date.


Frequently asked questions

Is my email checker a free email verifier?

Most email checkers allow doing some free checks if the email is real (usually, some dozens of them per day, week, or month). To receive functionality of bulk check or to expand the number of checks per time, you have to pay according to the subscription plan of your tool.


Is the ‘Okay’ status of a checked email means it will not bounce my letter?

Not in all cases. But, as a rule, sending letters to only ‘good’ addresses will reduce the bounce rate maximally – to 0%… 10% (with average 2.5%-5%). 


Is a letter sent to check email online? 

No, all data to check email is gathered based on the sequence of small commands that online email verifying software exchanges with a domain server of an email address and it does not result in sending any letter to anybody. It is similar to a ‘ping’ option if you know what that is.


I have hundreds of thousands of e-addresses to lookup. Does it mean I have to make it all by hand?

No. There is an option of bulk check in most email checkers but it is not free of charge. Some Gmail checkers accept up to 100,000 emails in one batch and give the result in a matter of minutes or a few hours. With hands, it would be impossible to verify does this email exist if you had that many of them.


How paid checks differ from free ones?

In many ways. For instance, it could take 5-15 seconds to check a single email for free, while in a batch, it would take only a fracture of a second for each individual one. Also, the number of made verifications and data gathered within a single check can differ. And, finally, there is a number limit of checks that a user can do for free. 

Included free with every account.

  • Instant Bounce Analysis

    Test your data. We’ll report back whether it’s OK to send or needs to be cleaned. Any size.

  • Testing for New Users

    Get 1,000 free verifications when you sign up. Test single emails, a bulk list, or our API.

  • Awesome Support & Security

    We pride ourselves on consistent service and availability; we’re here to help.

Common Questions About Email Verification

You may still have some questions about the email verification process. The following are some of the more common FAQs. The answers here will help you better understand the full value of our tool. If you still have questions after reviewing this section, feel free to visit our Help Desk or contact our Customer Success Team; we’re always happy to hear from you.

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Other Useful Steps to Improve Email Deliverability

Making sure your emails are properly delivered is important. Thus, senders should also consider taking these steps before sending emails to followers:

By taking these steps and using NeverBounce, you’ll be much more likely to consistently deliver emails. Luckily, our single email checker is both thorough and efficient. All you have to do is integrate it with your platform to ensure anyone who signs up for your newsletter is actually providing a valid address. This is important in the competitive field of email marketing.

Don’t let a poor sender reputation prevent you from reaching your followers. Create your NeverBounce account and start using our email and bounce checker today!

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