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

aid: mailboxlayer
name: mailboxlayer
description: >-
  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.
url: https://mailboxlayer.com
image: https://mailboxlayer.com/site_images/mailboxlayer_logo_white.svg
specificationVersion: '0.20'
created: '2026-05-28'
modified: '2026-05-30'
x-source: public-apis/public-apis
x-category: Email
x-tier: 3
x-tier-reason: bulk-registered-from-public-apis
x-type: company
tags:
  - Email
  - Email Verification
  - Email Validation
  - SMTP
  - MX Records
  - Catch-All Detection
  - Disposable Email
  - Free Email Provider
  - Role Address
  - Quality Score
  - apilayer
  - Public APIs
apis:
  - name: mailboxlayer Verification API
    description: >-
      REST JSON API for verifying a single email address. Performs syntax validation, MX-record lookup, real-time SMTP
      check, catch-all detection, role-address detection, free / disposable provider detection, did-you-mean suggestion,
      and a 0.0 - 1.0 deliverability quality score.
    humanURL: https://mailboxlayer.com
    baseURL: https://apilayer.net/api
    tags:
      - Email Verification
      - SMTP
      - MX Records
      - Quality Score
    properties:
      - type: Documentation
        url: https://docs.apilayer.com/mailboxlayer/docs/api-documentation
      - type: APIReference
        url: https://docs.apilayer.com/mailboxlayer/docs/api-documentation
      - type: Quickstart
        url: https://mailboxlayer.com/quickstart
      - type: Authentication
        url: https://docs.apilayer.com/mailboxlayer/docs/api-documentation
      - type: OpenAPI
        url: openapi/mailboxlayer-openapi.yml
      - type: JSONSchema
        url: json-schema/mailboxlayer-check-result-schema.json
      - type: JSONSchema
        url: json-schema/mailboxlayer-error-schema.json
      - type: JSONStructure
        url: json-structure/mailboxlayer-check-result-structure.json
      - type: JSON-LD
        url: json-ld/mailboxlayer-context.jsonld
      - type: Example
        url: examples/mailboxlayer-check-success-example.json
      - type: Example
        url: examples/mailboxlayer-check-typo-example.json
      - type: Example
        url: examples/mailboxlayer-check-disposable-example.json
      - type: Example
        url: examples/mailboxlayer-check-error-example.json
      - type: Example
        url: examples/mailboxlayer-check-result-example.json
      - type: Example
        url: examples/mailboxlayer-check-result-free-example.json
      - type: RateLimits
        url: rate-limits/mailboxlayer-rate-limits.yml
common:
  - type: Website
    url: https://mailboxlayer.com
  - type: Portal
    url: https://mailboxlayer.com/dashboard
  - type: SignUp
    url: https://mailboxlayer.com/product
  - type: Pricing
    url: https://mailboxlayer.com/product
  - type: GettingStarted
    url: https://mailboxlayer.com/quickstart
  - type: TermsOfService
    url: https://mailboxlayer.com/terms
  - type: PrivacyPolicy
    url: https://mailboxlayer.com/privacy
  - type: Support
    url: https://mailboxlayer.com/support
  - type: GitHubOrganization
    url: https://github.com/apilayer
  - type: GitHubRepository
    url: https://github.com/apilayer/mailboxlayer-API
  - type: SDK
    name: Laravel mailboxlayer
    url: https://github.com/ash-jc-allen/laravel-mailboxlayer
  - type: SDK
    name: actfong/mailboxlayer (Ruby)
    url: https://github.com/actfong/mailboxlayer
  - type: SDK
    name: damienmarchandfr/mailboxlayer-node-client (Node/TypeScript)
    url: https://github.com/damienmarchandfr/mailboxlayer-node-client
  - type: SDK
    name: mailboxlayerbundle (Symfony)
    url: https://github.com/ylly/mailboxlayerbundle
  - type: Integrations
    name: PostHog
    url: https://github.com/PostHog/mailboxlayer-plugin
  - type: Integrations
    name: Fortinet FortiSOAR
    url: https://github.com/fortinet-fortisoar/connector-mailboxlayer
  - type: SpectralRules
    url: rules/mailboxlayer-rules.yml
  - type: Vocabulary
    url: vocabulary/mailboxlayer-vocabulary.yml
  - type: PublicAPIsListing
    url: https://github.com/public-apis/public-apis
  - type: Plans
    url: plans/mailboxlayer-plans-pricing.yml
  - type: RateLimits
    url: rate-limits/mailboxlayer-rate-limits.yml
  - type: FinOps
    url: finops/mailboxlayer-finops.yml
  - type: Features
    data:
      - name: Syntax And Typo Check
        description: Thorough RFC 5322 syntax validation with did-you-mean suggestions for likely typos.
      - name: Real-Time SMTP Verification
        description: Each address is pinged via SMTP to confirm the mailbox actually accepts mail.
      - name: MX Record Lookup
        description: Verifies that the email domain has functioning MX records.
      - name: Catch-All Detection
        description: Determines whether the recipient domain accepts mail for any local part (paid plans only).
      - name: Role Address Detection
        description: Flags addresses associated with a function rather than a person (support@, admin@, etc.).
      - name: Free Provider Detection
        description: Identifies addresses on free webmail providers (Gmail, Yahoo, Outlook.com, etc.).
      - name: Disposable Provider Detection
        description: Identifies addresses on throwaway / disposable providers (mailinator.com, etc.).
      - name: Quality Score
        description: A 0.0 to 1.0 numeric score expressing overall deliverability and quality.
      - name: HTTPS Encryption
        description: 256-bit HTTPS transport on paid plans (Basic and above).
      - name: Bulk Endpoint
        description: Submit 25 addresses (Pro Plus) or 100 addresses (Enterprise Plus) in a single request.
      - name: JSONP Support
        description: JSONP wrapper via the `callback` query parameter.
  - type: UseCases
    data:
      - name: Signup Form Validation
        description: Catch typos and disposable addresses at signup before they hit your user database.
      - name: List Hygiene
        description: Clean existing email marketing lists to lift deliverability and sender reputation.
      - name: Lead Enrichment
        description: Enrich CRM and lead-capture records with deliverability scores and role flags.
      - name: Fraud And Abuse Prevention
        description: Block disposable email providers commonly used for trial abuse and chargebacks.
      - name: Transactional Email Hygiene
        description: Reduce hard-bounces from order receipts, password resets, and notifications.
      - name: B2B Sales Qualification
        description: Separate role addresses and free-provider addresses from individual corporate inboxes.
  - type: Integrations
    data:
      - name: PostHog
        description: Plugin scoring incoming PostHog user emails via the mailboxlayer API.
      - name: Fortinet FortiSOAR
        description: Connector for incorporating email verification into security orchestration playbooks.
      - name: Laravel
        description: Multiple community Laravel packages wrap mailboxlayer for PHP web applications.
      - name: Symfony
        description: Symfony bundle for mailboxlayer-backed email validation.
      - name: Node.js / TypeScript
        description: Node and TypeScript client libraries for serverside email verification.
      - name: Ruby
        description: Ruby client gem.
      - name: Delphi
        description: Delphi sample demonstrating the API for desktop application validation.
  - type: Solutions
    data:
      - name: Free
        description: 100 requests/month, HTTP only, no support, no catch-all detection.
      - name: Basic
        description: $14.99/mo for 5,000 requests; HTTPS, catch-all detection, standard support.
      - name: Professional Plus
        description: $74.99/mo for 50,000 requests; adds bulk endpoint (25 emails).
      - name: Enterprise Plus
        description: $249.99/mo for 250,000 requests; adds bulk endpoint (100 emails) and richer SLAs.
      - name: Custom
        description: Contact sales for higher volumes and bespoke arrangements.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com

mailboxlayer

APIs

mailboxlayer Verification API

Features

Use Cases

Integrations

Solutions

Semantic Vocabularies

Mailboxlayer Context

API Governance Rules

mailboxlayer API Rules

Resources

Sources