mailboxlayer

mailboxlayer is an apilayer-owned REST JSON API for email address verification. It performs syntax and typo checks, MX-record lookup, real-time SMTP verification, catch-all detection, role-address detection, free and disposable provider detection, and returns a numeric deliverability quality score. Useful for signup-form validation, list hygiene, lead enrichment, and fraud prevention.

1 APIs 11 Features

EmailEmail VerificationEmail ValidationSMTPMX RecordsCatch-All DetectionDisposable EmailFree Email ProviderRole AddressQuality ScoreapilayerPublic APIs

Real-Time SMTP Verification

Each address is pinged via SMTP to confirm the mailbox actually accepts mail.

MX Record Lookup

Verifies that the email domain has functioning MX records.

Catch-All Detection

Determines whether the recipient domain accepts mail for any local part (paid plans only).

Role Address Detection

Flags addresses associated with a function rather than a person (support@, admin@, etc.).

Free Provider Detection

Identifies addresses on free webmail providers (Gmail, Yahoo, Outlook.com, etc.).

Disposable Provider Detection

Identifies addresses on throwaway / disposable providers (mailinator.com, etc.).

Quality Score

A 0.0 to 1.0 numeric score expressing overall deliverability and quality.

HTTPS Encryption

256-bit HTTPS transport on paid plans (Basic and above).

Bulk Endpoint

Submit 25 addresses (Pro Plus) or 100 addresses (Enterprise Plus) in a single request.

JSONP Support

JSONP wrapper via the `callback` query parameter.

Use Cases

Signup Form Validation

Catch typos and disposable addresses at signup before they hit your user database.

List Hygiene

Clean existing email marketing lists to lift deliverability and sender reputation.

Lead Enrichment

Enrich CRM and lead-capture records with deliverability scores and role flags.

Fraud And Abuse Prevention

Block disposable email providers commonly used for trial abuse and chargebacks.

Transactional Email Hygiene

Reduce hard-bounces from order receipts, password resets, and notifications.

B2B Sales Qualification

Separate role addresses and free-provider addresses from individual corporate inboxes.

Integrations

PostHog

Plugin scoring incoming PostHog user emails via the mailboxlayer API.

Fortinet FortiSOAR

Connector for incorporating email verification into security orchestration playbooks.

Laravel

Multiple community Laravel packages wrap mailboxlayer for PHP web applications.

Symfony

Symfony bundle for mailboxlayer-backed email validation.

Node.js / TypeScript

Node and TypeScript client libraries for serverside email verification.

Ruby

Ruby client gem.

Delphi

Delphi sample demonstrating the API for desktop application validation.

Solutions

Free

100 requests/month, HTTP only, no support, no catch-all detection.

Basic

$14.99/mo for 5,000 requests; HTTPS, catch-all detection, standard support.

Professional Plus

$74.99/mo for 50,000 requests; adds bulk endpoint (25 emails).

Enterprise Plus

$249.99/mo for 250,000 requests; adds bulk endpoint (100 emails) and richer SLAs.

Custom

Contact sales for higher volumes and bespoke arrangements.

GitHubOrganization

PublicAPIsListing

Sources

opencollection: 1.0.0
info:
  name: mailboxlayer API
  version: 1.0.0
request:
  auth:
    type: apikey
    key: access_key
    value: '{{access_key}}'
    placement: query
items:
- info:
    name: Verification
    type: folder
  items:
  - info:
      name: Verify Email Address
      type: http
    http:
      method: GET
      url: https://apilayer.net/api/check
      params:
      - name: access_key
        value: ''
        type: query
        description: Your mailboxlayer API access key.
      - name: email
        value: ''
        type: query
        description: The email address to verify.
      - name: smtp
        value: ''
        type: query
        description: Set to `0` to skip the real-time SMTP check (default `1`).
      - name: format
        value: ''
        type: query
        description: Set to `1` to pretty-print the JSON response (default `0`).
      - name: callback
        value: ''
        type: query
        description: JSONP callback function name. Wraps the JSON response in a function call.
    docs: 'Verifies a single email address. Performs syntax validation, MX-record

      lookup, SMTP verification (optional), catch-all detection, role-address

      detection, free-provider detection, disposable-provider detection,

      did-you-mean suggestion, and returns a deliverability quality score.

      '
bundled: true

mailboxlayer

APIs

mailboxlayer Verification API

Collections

mailboxlayer API

Pricing Plans

Mailboxlayer Plans Pricing

Rate Limits

Mailboxlayer Rate Limits

FinOps

Mailboxlayer Finops

Features

Use Cases

Integrations

Solutions

Semantic Vocabularies

Mailboxlayer Context

API Governance Rules

mailboxlayer API Rules

JSON Structure

Mailboxlayer Check Result Structure

Example Payloads

Mailboxlayer Check Disposable Example

Mailboxlayer Check Error Example

Mailboxlayer Check Result Example

Mailboxlayer Check Result Free Example

Mailboxlayer Check Success Example

Mailboxlayer Check Typo Example

Resources

Sources