Email Verification Tool | Verify Address Validity | WhoisXML API

#1 Email Verification Tool to verify the existence and legitimacy of email addresses

Our online email verifier tool lets you find out instantly about the validity, existence, and quality of any email address via lookup queries. Reduce bounce rates, avoid spam traps, and screen new user registrations in real-time.

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

About our email validation tool

Email Verification Lookup performs various email address checks for syntax errors, free and disposable addresses, mail server and mailbox existence, and more.

  • Identify free email service providers

    Email Verification Lookup checks if an address was created using a free email service. Such addresses are unlikely to be used in a business environment.

  • Automatically detect disposable email addresses

    Spot abusive users who attempt to sign up with disposable email addresses from Mailinator, 10MinuteMail, GuerrillaMail, or other 2,000 known disposable email service providers.

  • Avoid syntax errors

    Easily detect invalid email addresses that do not follow prescribed Internet Engineering Task Force (IETF) formats with Email Verification Lookup’s complete syntactic email validation engine.

  • Verify the existence of an address’s mail server

    Every valid email address should have a corresponding mail server with its own DNS MX record. Email Verification Lookup can check if an email address has such records and therefore exists.

  • Ensure mailbox existence

    Email Verification Lookup’s email-sending emulation and SMTP connection techniques let you verify if an address is able to receive emails.

  • Notice catch-all email addresses

    Email Verification Lookup detects catch-all email addresses that are not assigned to a specific individual and may result in hard bounces.

Who can benefit from an email verification tool?

Email Marketers

Email Marketers

Check any suspicious email address with email verification checks to avoid the hazards of inexistent and invalid email addresses.

Email validation is helpful to drive down your bounce rate, make it less likely to fall for spam traps and end up on someone’s blocklist, and effectively reach your customers to improve both your deliverability and ROI.

Cybersecurity and Brand Protection Specialists

Email validation is a healthy practice from a cybersecurity standpoint in that it helps detect malicious actors who often hide behind erroneous or disposable email addresses to execute phishing and spamming attacks while preserving their anonymity.

Consistently verifying email addresses also contribute to your domains’ reputability. Being flagged by third parties as a spammer or ending up on a blacklist as a result of suboptimal email practices can severely damage your reputation and affect operations.

Cybersecurity and Brand Protection Specialists
SaaS & Website Managers

SaaS & Website Managers

Website business owners and SaaS managers can benefit from Email Verification Lookup to reduce the likelihood of faulty signups and identify B2B leads based on their use of business-branded email addresses.

Illegitimate users who deliberately entered a wrong email address or used a disposable one may be there to abuse your freemium features. They take up your system resources with no intention of ever upgrading and contributing to your ROI.

Disposable Email Domains Data Feed

Check Our Disposable Email Domains Data Feed

Find all disposable email domains in our database, covering most temporary email service providers. Our data is accurate and updated daily.

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