Email Verification API | Address validation service | WhoisXML API

#1 Email Verification API to verify the existence, validity & quality of any email address

Our Email Verification API performs a comprehensive validation of email addresses in real-time and conveniently. Verify the email addresses coming from new user registrations, reduce email bouncing, block spam, and more.

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1,000 free API requests monthly. No credit card required.

301,014,459Email addresses verified
2,489Satisfied customers
18,016,895Bounce backs prevented

Our email validation service via API calls checks:

  • Syntax

    Check if the email address conforms to the IETF standards by using a complete syntactic email validation engine.

  • If the address is branded

    Check if the address is custom and linked to a business email account or if it is generic and coming from a free email service.

  • If the address is disposable

    Check if the email address is supplied by a known disposable email address provider such as Mailinator, 10MinuteMail, GuerrillaMail, and 2,000+ more.

  • Mail server existence

    Check for the availability of email addresses’ corresponding domains by ensuring the existence of DNS MX records.

  • Mailbox existence

    Check if the email address exists and can receive emails via the Simple Mail Transfer Protocol (SMTP) through email-sending emulation techniques.

  • Use as a catch-all email address

    Check if the email address can receive emails for more than one email address.

What is an Email Verification API?

An email verification API, also known as an email validation API, is a means for developers and product architects to integrate email checking capabilities into existing software and applications via API calls using different programming languages.

What isEmail VerificationAPI?

Practical usage

Improve marketing campaign results

Improve marketing campaign results

In email marketing, it is important that the emails you send are verified, validated, and received by customers. One of the most common causes of email bouncing is sending to unverified email addresses.

By eliminating bounced emails and utilizing email verification and email validation tools, you can increase your sender score and email campaign quality.

Ensure that users who sign up to your website have a valid and verified email address

  • You can use our email verification services to check that someone signing up to your service is doing so using a business-branded email address.
  • Stay in touch with subscribers and use their verified email addresses to warn them of their payment card expiration, send them receipts, offer them new features or products, and more.
  • Enables your users to reset their password securely should they forget it.
  • Helps verify someone’s identity automatically without relying on manual human checks.
Ensure that users who sign up to your website have a valid and verified email address
Segment potentially dangerous emails

Segment potentially dangerous emails

  • Keep potentially unverifiable email addresses such as disposable ones out of your contact list. Users signing up for freemium services with disposable email addresses may turn out to be abusers.
  • Avoid entanglements with cybercriminals and fraudsters who hide behind fake personal or business email addresses.
Disposable Email Domains Data Feed

Interested in lists of disposable email domains?

Use our disposable email domains data feed to catch potential abusers red-handed. We provide reliable and up-to-date data in a format that is compatible with most systems.

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Simplify your work

Email Verification client library in PHP language Node.js Email Verification client library Email Verification client library in Python language Flask Email Verification client library Express.js Email Verification client library

Integrating Email Verification API in a way that matches your system requirements is easy with our readily available client libraries.

Go to libraries
Email Verification API

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Enterprise API Packages

API access through WhoisXMLAPI can be purchased as an annual subscription. The access pricing is based on the number of queries, which is measured monthly with per-minute rate limits. The pricing structure gives predictability to business planning and solution architecture.

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