Mailboxlayer API


Mailboxlayer is a lightweight yet powerful RESTful JSON API that performs real-time email validation and verification. It helps developers instantly assess the quality and deliverability of email addresses with precision—checking syntax, detecting typos, verifying MX and SMTP records, identifying catch-all and role-based addresses, and filtering out free or disposable providers while offering a deliverability score. It’s secure (256-bit HTTPS) and built by APILayer, trusted for making cleanliness and accuracy easy in user data collection.

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API Documentation

Mailboxlayer offers a simple REST-based JSON API that enables you to thoroughly check and verify email addresses at the point of entry into your system.

In addition to checking the syntax, the actual existence of an email address using MX-Records and the Simple Mail Transfer Protocol (SMTP), and detecting whether or not the requested mailbox is configured to catch all incoming mail traffic, the Mailboxlayer API is linked to a number of regularly updated databases containing all available email providers, which simplifies the separation of disposable (e.g. "mailinator") and free email addresses (e.g. "gmail", "yahoo") from individual domains.

Combined with typo checks, did-you-mean suggestions, and a numeric score reflecting the quality of each email address, these structures will make it simple to filter automatically "real" customers from abusers and increase response and success rates of your email campaigns.

Endpoint Summary

EndpointDescriptionAvailability
/checkValidate a single email address with full metadata
/bulk_checkValidate multiple email addresses in one request

Why Choose Mailboxlayer?

  • Simplicity: One endpoint handles all validations, with straightforward URL parameters.
  • Comprehensive: Syntax, existence, provider, and catch-all detection—plus scoring in one JSON response.
  • Bulk Support: Efficient for processing lists of emails in one go (with higher-tier plans)
  • Affordable & Secure: Free tier available; paid plans start at ~$7.99–$14.99/month with secure, encrypted delivery

 

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