How do result quality levels work?

Verifalia’s industry-leading email validation comes in three different quality levels available with each account: Standard, High and Extreme quality.

We help you and other email marketers or entrepreneurs to adopt best practices for your email lists: Verifalia services are unbeatable and perform on an engine that has been continually updated since 2006.

We validate addresses that our competitors can't.

Our sophisticated techniques provide unparalleled results, allowing only Verifalia to navigate old servers, slow servers and the world's most sophisticated anti-spam systems.

What quality level does Verifalia offer?

Each Verifalia account – including those running on our Free plan – allows to decide which quality level to use before validating email addresses, either on the Verifalia dashboard or through our email verification API.

Our email validation engine adapts its processing logic in order to obey to the chosen quality level: the higher the quality level, the higher the percentage of definite results it returns even for the most problematic email addresses and mail exchangers.

Generally speaking, our quality levels differ on the number of validation passes they offer and on the maximum anti-tarpit time they support, where more validation passes increase the definite results one can get for temporary issues – e.g. a full mailbox, a transient mail exchanger error or a greylisting in place – and a higher anti-tarpit time allows to validate even against really slow mail exchangers.

Learn more about how our Validation passes and SMTP Tarpits work.

Let’s explore all quality levels you can get for your validations:

  • Standard Quality features a single validation pass and 5 second anti-tarpit / graylisting time. It suits most businesses’ needs and provides good results for the vast majority of email addresses;
  • High Quality is marked by its 3 validation passes and 50 seconds of anti-tarpit / graylisting time. Permits a validation of most of the addresses, even those with temporary issues or slower mail exchangers;
  • Extreme Quality, thanks to its top-notch quality, is designed for professionals and performs email validation at the highest level with 9 validation passes and 2 minutes of anti-tarpit / graylisting time.

Before validating your addresses through the Verifalia dashboard or upon submitting your lists using the Verifalia API (in the event you are a developer), you can choose the results quality level that suits better your business needs.

Which is the most suitable validation quality level for me?

It most of the times happen that the Standard quality suits common business needs and permits an efficient list cleaning or real-time validation.

Of course, if you need a higher percentage of definitive result and you prefer that your emails pass:

… you better choose our High or Extreme Quality and take advantage of the best results this industry has to offer!
With that being said, the more accurate is the results you require, the higher level of service you should choose.

Do higher level service use more credits than the Standard one?

Each email validation has a clear-cut unit price, depending on the quality of results you need:

Standard quality level: 125 validations per credit, that is: 0.008 credits per validation.
High quality level: 50 validations per credit, that is: 0.02 credits per validation.
Extreme quality level: 25 validations per credit, that is: 0.04 credits per validation.

For a complete overview of our pricing, please see our Verifalia pricing page.

Can I test all quality levels before paying?

Yes: of course you can! Sign Up Free and get your 0.2 daily free credits, so each day of subscription you can verify email addresses on a Standard, High and Extreme quality service!

Our free account is not a trial: it is a free plan that gives you ongoing access to our client dashboard, allows to upload email lists for validation, permits to automate your email hygiene with the Verifalia API, and much more.


Not sure about which quality level meets your specific needs?
We can help: just Contact us.


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