Email verification guides

Choose your stack, interpret a verification result, or investigate a mail-routing problem.

Run your first email check

Create an account, confirm your email, then create a project and save its key. Your first project gets 1,000 free credits, once per account. No card required.

curl --fail-with-body --max-time 30 https://emailverifier.dev/api/v1/verify --header 'X-API-Key: YOUR_API_KEY' --header 'Content-Type: application/json' --data '{"email":"demo@gmail.com"}'

Replace YOUR_API_KEY with your project key and run in a Bash-compatible terminal. Each request uses one credit. An unknown result means the mailbox evidence is inconclusive.

Copy request
Set the key for Node.js or Python

Replace YOUR_API_KEY below. This sets the key for your current terminal session.

Bash (macOS or Linux)

export EMAILVERIFIER_API_KEY='YOUR_API_KEY'

PowerShell (Windows)

$env:EMAILVERIFIER_API_KEY = 'YOUR_API_KEY'

Node.js

Node.js 22+. No packages to install. Set EMAILVERIFIER_API_KEY in your local environment, then run:

node verify-email.mjs person@example.com
Download verify-email.mjs

Python

Python 3.10+. No packages to install. Set EMAILVERIFIER_API_KEY in your local environment, then run:

python verify-email.py person@example.com
Download verify-email.py

The examples print the real API response and stop on HTTP errors. Use action to decide whether to allow, review, or block. See how to handle API results in production before adding account creation.

Understand verification results

Separate address checks, mailbox evidence, and proof that a person controls an inbox.

Add verification to your signup flow

Keep the API key on your server and handle allow, review, and block decisions before creating an account.

Verify lists and automate checks

Connect verification to workflows, AI agents, spreadsheets, and CSV imports.

Diagnose mail routing and delivery

Read DNS and SMTP evidence without treating a timeout or policy block as an invalid mailbox.

Make your first API request

Create an account, confirm your email, then create a project and copy its API key. Your first project gets 1,000 non-expiring credits, with no card required. Each email or domain check with your key uses one credit.

Get 1,000 free creditsREST API referenceTry the free tools

Browse the full blog archive for more email infrastructure articles.