Free Email Tools

Test mail servers, check DNS records and fix email authentication. Every tool is free, needs no account, and DNS lookups run directly in your browser.

SMTP Server Testing

SMTP Test Tool

Open a live SMTP session, test TLS and authentication, and send a test email

DNS & Email Authentication

MX Lookup

Find the mail servers for a domain, their priority, IPs and email provider

SPF Record Checker

Validate an SPF record, count DNS lookups and expand every include

SPF Record Generator

Build a valid SPF record for Google Workspace, Microsoft 365, SES and more

DMARC Record Checker

Look up and explain a domain's DMARC policy, reporting and alignment

DMARC Record Generator

Create a DMARC TXT record with policy, reports and alignment settings

DKIM Record Checker

Check a DKIM selector, read the public key and its length, or scan common selectors

Addresses & Messages

Email Validator

Verify email format, check syntax, and detect disposable addresses

Email Header Analyzer

Parse headers, trace routes, and check SPF/DKIM/DMARC

Where to Start

Mail not arriving at your domain? Run an MX lookup, then test the server with the SMTP Test Tool.
Your mail lands in spam? Check SPF, DKIM and DMARC, and read the results of a real message with the header analyzer.
Setting up a new domain? Create records with the SPF generator and DMARC generator.
Cleaning a mailing list? Use the email validator to catch typos and disposable addresses.