Email Checker

Email Checker

Email Verification – What’s in a Good Email Checker?

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Email verification is the process of checking email addresses to confirm they represent real people who can receive emails. Maintaining a clean, validated subscriber list is important for email marketers because list hygiene has a direct effect on sender reputation and email deliverability.

An email verifier, or email checker, is a tool that confirms the authenticity of an email address. The checker verifies items such as formatting and domain validity and then flags—or in some cases removes—invalid addresses from a subscriber list.

Top-tier email verification applications go beyond simply removing bad addresses from a list to provide more detail about the quality of addresses. These tools include APIs that enable integrations with marketing platforms and email service providers (ESPs) so bad addresses are suppressed before they can affect the deliverability of marketing campaigns.

Discover how BriteVerify checks the email addresses on your list so you can remove faulty addresses before you send to them.

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How does email verification differ from email deliverability?

Email delivery refers to whether, and how, an email is accepted by mailbox providers (MBPs) like Gmail, Microsoft, and Yahoo. Email deliverability refers to whether an email is delivered to the inbox or filtered to the spam folder. When determining how to handle incoming email, MBPs check incoming email for identifiers, such as:

  • Sender reputation
  • Domain/IP reputation
  • Email engagement metrics, including bounce rates and spam complaints
  • Email authentication
  • Email content
  • Impersonation protection

Senders with clean data and a good reputation are more likely to have email delivered to the inbox. If a sender has a poor reputation score or a high bounce rate, MBPs often place their email in the spam folder or block the message altogether. This makes deliverability a key metric for marketers to understand since it has a direct effect on their email campaign visibility and their ability to generate conversions.

Learn more about Email Deliverability and how it affects the performance of all your email marketing activity.

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Why it is important to verify email addresses?

It takes time and effort for businesses to acquire customer information, but not every email address maintains its value as the list ages. A successful email program is closely tied to having a healthy, clean email list because list hygiene is a top priority for MBPs.  

Email addresses can be invalid when they are first entered, as in the case of fake or misspelled addresses submitted through web forms. Addresses also become outdated as subscribers change jobs, close old accounts, or domains get turned off. Leaving these risky emails on a list can result in higher bounce rates and cause deliverability challenges. 

Effective list hygiene practices have become even more critical with the introduction of Apple’s Mail Privacy Protection. Open rates are no longer a reliable measurement of subscriber engagement which makes recency management less accurate. Therefore, ongoing validation of your lists is essential to identify inactive subscribers.

Marketers can also acquire email addresses through outside sources, like partnerships or third-party relationships. Sending to bad addresses indicates to MBPs that a sender is employing risky acquisition practices, which makes validation even more important when addresses come from these external resources. A single list from an outside source can lead to many spam complaints if the partnership did not make it clear that those subscribers were opting in to receive emails.

Learn more about Apple’s Mail Privacy Protection and how it impacts your inactives strategy.

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How email verification works

Email verification runs several checks on an address to verify that it can receive mail. Most standard email checkers validate the following items: 

  • Format: Addresses use correct formatting like “[email protected]” 
  • Gibberish Check: Addresses are not composed of random numbers, letters, or symbols. 
  • Domain Check: The domain exists and is not invalid. 
  • MX Record Request: There is an MX record available for the domain and it can receive emails. 
  • Disposable Addresses: The domain name is not used for temporary email addresses. 
  • SMTP Check: Determines whether the address will bounce. 
  • Accept-all Domain: Also known as “catch-all” email domains, these will receive any email that is sent to them. It is risky to send to addresses on these domains because there is no way to be confident they are invalid without sending a live email and having it bounce.
Addresses that fail these checks are then either removed from the list or flagged so marketers can suppress them from future campaigns. 
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Choosing the right verification tool

While there are many tools that can be used to check the authenticity of an email address, some provide more value than others. 
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What to look for

  1. Real-time data processing: The verification tool should be able to validate addresses as soon they are added to the list. Delays between email acquisition and email validation lead to higher entry errors that result in bounced messages or spam complaints.
  2. Bulk validation: Users should be able to quickly validate large lists of hundreds, thousands, or millions of addresses in minutes or hours.
  3. Reporting: The tool should identify how many addresses are from invalid or unknown domains, were rejected due to invalid formatting, or come from accept-all domains. Detailed reports can provide insight into low-quality acquisition sources.
  4. Integration: The tool should connect directly with a marketer’s ESP, ideally through an API. A tool that also integrates with CRM systems can provide additional value by ensuring sales teams aren’t contacting inactive addresses.
  5. Security: Email addresses that are validated should not be shared, resold, or used in any way by the validation provider. Look for tools that guarantee compliance with GDPR, CCPA and other privacy laws.
  6. Support: It is important to have easy access to a, responsive support team when questions arise, either during integration or as part of an ongoing validation process.
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What to avoid

  1. Inaccurate results: A good list checker should be able to provide a level of accuracy above 95%. Anything below that can negatively impact your sender reputation.
  2. One-time validation: While a single list validation identifies bad addresses, it doesn’t prevent more from being added to the file. Without real-time validation, a clean list can quickly become filled with inactive subscriptions.
  3. Slow processing times: Hours or days spent validating small lists means less time to spend on list segmentation or contacting customers.
  4. Complicated User Interface: Tools with a poor user experience are less likely to be used consistently. Users should be able to easily navigate any list validation application.
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FAQ about Email Verification and Checking

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How can I verify email addresses?

Use an email verification tool to check that a list contains valid email addresses. 
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What does an email verifier check?

An email verifier, or email checker, determines if addresses on a subscriber list are valid and belong to a real person or if they’re likely to bounce. 
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Can I verify email lists?

Yes, email verification tools can check single addresses and large lists of thousands or millions of addresses.
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Can a verified address bounce?

Yes, bounces can still occur if a subscriber has a full inbox or if the receiving server is not responding. Oftentimes, senders might see false-positive hard bounces. Email verification can help marketers avoid suppressing good addresses in error.
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Will a verifier remove spam traps from my list?

No, spam traps are still valid addresses that can receive email. A verifier will not identify spam traps. However, spam traps can be suppressed by using good list hygiene processes to clean subscriber lists.
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How accurate are email verification results?

Results from a good email checker should be at least 95% accurate.
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Every company that depends on email marketing should have a method for checking the accuracy of their email list. BriteVerify has over a decade of experience with data validation, providing insight and reporting about the health of your list.

Discover how Validity BriteVerify can help you build and maintain an actionable email database so you can reach and engage more people.