Hunter Email Verifier API

Verify the deliverability of an email address through MX-record inspection, SMTP connection checks, catch-all detection, disposable-domain detection, webmail detection, and Hunter's own database lookup. Returns a normalized status (valid, invalid, accept_all, webmail, disposable, unknown) plus a 0-100 confidence score. May return 202 while verification is in flight.

Hunter Email Verifier API is one of 8 APIs that Hunter publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

This API exposes 1 machine-runnable capability that can be deployed as REST, MCP, or Agent Skill surfaces via Naftiko and 1 JSON Schema definition.

Tagged areas include Email Verifier and Deliverability. The published artifact set on APIs.io includes API documentation, an OpenAPI specification, 1 Naftiko capability spec, and 1 JSON Schema.

OpenAPI Specification

hunter-email-verifier-api-openapi.yml Raw ↑
openapi: 3.1.0
info:
  title: Hunter Email Verifier API
  description: >
    Verifies the deliverability of an email address by performing MX-record
    inspection, SMTP connection checks, catch-all detection, disposable domain
    detection, webmail detection, and Hunter's own database lookup. Returns a
    confidence score and a normalized status (valid, invalid, accept_all, webmail,
    disposable, unknown).
  version: v2
  contact:
    name: Hunter Support
    url: https://hunter.io/contact
  license:
    name: Hunter Terms of Service
    url: https://hunter.io/terms
servers:
  - url: https://api.hunter.io/v2
    description: Production
security:
  - ApiKeyQuery: []
  - ApiKeyHeader: []
  - BearerAuth: []
tags:
  - name: Email Verifier
    description: Verify the deliverability of an email address.
paths:
  /email-verifier:
    get:
      summary: Hunter Verify Email
      description: >
        Verifies an email address against MX, SMTP, regex, gibberish, disposable,
        webmail, accept-all, block, and Hunter database checks. Returns a status,
        score, and supporting flags. Responds 202 while verification is still in
        flight; retry the same call to get the final result.
      operationId: emailVerifier
      tags:
        - Email Verifier
      parameters:
        - name: email
          in: query
          required: true
          description: The email address to verify.
          schema: { type: string, format: email, example: [email protected] }
        - $ref: '#/components/parameters/ApiKeyQuery'
      responses:
        '200':
          description: Verification result.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/EmailVerifierResponse'
        '202':
          description: Verification still processing; retry the same request.
        '400':
          $ref: '#/components/responses/Error'
        '451':
          description: Personal-data restriction prevents verification.
        '429':
          $ref: '#/components/responses/Error'
components:
  securitySchemes:
    ApiKeyQuery: { type: apiKey, in: query, name: api_key }
    ApiKeyHeader: { type: apiKey, in: header, name: X-API-KEY }
    BearerAuth: { type: http, scheme: bearer }
  parameters:
    ApiKeyQuery:
      name: api_key
      in: query
      required: true
      description: Your Hunter API key.
      schema: { type: string }
  schemas:
    EmailVerifierResponse:
      type: object
      properties:
        data:
          type: object
          properties:
            status: { type: string, enum: [valid, invalid, accept_all, webmail, disposable, unknown] }
            result: { type: string, description: 'Deprecated. Use `status`.' }
            score: { type: integer, minimum: 0, maximum: 100 }
            email: { type: string, format: email }
            regexp: { type: boolean }
            gibberish: { type: boolean }
            disposable: { type: boolean }
            webmail: { type: boolean }
            mx_records: { type: boolean }
            smtp_server: { type: boolean }
            smtp_check: { type: boolean }
            accept_all: { type: boolean }
            block: { type: boolean }
            sources:
              type: array
              items:
                type: object
                properties:
                  domain: { type: string }
                  uri: { type: string }
                  extracted_on: { type: string, format: date }
                  last_seen_on: { type: string, format: date }
                  still_on_page: { type: boolean }
        meta:
          type: object
          properties:
            params:
              type: object
              additionalProperties: true
    Error:
      type: object
      properties:
        errors:
          type: array
          items:
            type: object
            properties:
              id: { type: string }
              code: { type: integer }
              details: { type: string }
  responses:
    Error:
      description: Error response.
      content:
        application/json:
          schema: { $ref: '#/components/schemas/Error' }