Help Center & API Documentation

Integrate Mailsfinder swiftly. Learn authentication, endpoints, limits, and best practices to find and verify emails reliably.

Get API Key Start Using API

Why Teams Choose Mailsfinder

Fast & Accurate Finder

Predicts work emails from name + domain and returns confidence scores.

Deliverability Checks

Multi-step verification to reduce bounces and protect reputation.

Clear JSON Responses

Clean, structured fields for easy parsing and automation.

Fair Rate Limits

Generous quotas with burst support to keep workflows smooth.

Getting Started

Step 1

Create account

Step 2

Get API key

Step 3

Use Finder or Verify

Overview

Mailsfinder offers two core endpoints: Email Finder to discover likely work emails based on name and domain, and Email Verification to validate deliverability, mailbox existence, and risk signals. Use your API key to authenticate requests and process at scale.

Email Finder

Predicts professional email formats and returns confidence scores.

Email Verification

Performs multi-step checks to ensure deliverability and reduce bounces.

Authentication

Authenticate by passing your API key via the Authorization header. Keep your keys secret and rotate regularly.

cURL

curl -X POST "https://server.mailsfinder.com/api/access-key/email/findEmail" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
  "first_name": "John",
  "last_name": "Doe",
  "domain": "example.com"
}'

Email Finder API

Endpoint

POST https://api.mailsfinder.com/v1/find/email

Headers

Authorization: Bearer YOUR_API_KEY

Request Body

curl -X POST "https://server.mailsfinder.com/api/access-key/email/findBulkEmail" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '[
  {
    "domain": "example.com",
    "first_name": "John",
    "last_name": "Doe"
  },
  {
    "domain": "example.com",
    "first_name": "Jane",
    "last_name": "Smith"
  }
]'

Sample Response

{
  "email": "jane.doe@acme.com",
  "confidence": 0.92,
  "pattern": "first.last",
  "sources": ["linkedin", "company_site"],
  "meta": { "discovered_at": "2026-01-04T10:15:00Z" }
}

Email Verification API

Endpoint

POST https://api.mailsfinder.com/v1/verify/email

Headers

Authorization: Bearer YOUR_API_KEY

Request Body

curl -X POST "https://server.mailsfinder.com/api/access-key/email/verifyEmail" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
  "email": "john.doe@example.com"
}'

Sample Response

curl -X POST "https://server.mailsfinder.com/api/access-key/email/verifyBulkEmail" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
  "emails": [
    "john.doe@example.com",
    "jane.smith@example.com"
  ]
}'

API Limits

Rate Limits

Up to 60 requests per minute per API key.

Payload

Max 1000 emails per bulk verification job.

Status Codes

200

All emails were processed.

400

The list you sent is incorrect or incomplete.

401

You are not logged in.

429

You sent too many requests at once.

500

Something went wrong while processing emails.

FAQs

You can generate your API key directly from your dashboard at app.mailsfinder.com after signing in. Once created, use this key to authenticate all API requests.

Our Email Finder provides up to 99% accuracy, using multiple verification layers including domain checks, MX records, and SMTP validation to ensure reliable results.

Yes, we fully support bulk email verification, allowing you to verify multiple email addresses in a single API request efficiently.

Rate limits are applied based on your API key and subscription plan. Each request consumes credits, and limits help ensure fair usage and system stability. If you exceed the allowed rate, requests may be temporarily throttled until limits reset.

Ready to integrate? Start using our API today.

Build workflows that find and verify emails reliably—clean lists, higher deliverability, and more replies.

Get API Key