Learn

Email verification and deliverability, explained.

Plain-language guides on how verification works, how email authentication protects your domain, and how to keep a list healthy.

Guides

Start here.

Fundamentals

What is email verification?

Email verification checks whether an address can receive mail without sending one: syntax, domain, mail servers and mailbox. Learn the checks and limits.

Read the guide →

Mail security

SPF, DKIM and DMARC explained

SPF lists who may send for your domain, DKIM signs messages, DMARC sets the policy. Learn the records, qualifiers, alignment and common mistakes.

Read the guide →

Mail security

DMARC from none to reject

A step-by-step plan to move a domain from no DMARC to p=reject: publish p=none with reports, align every sender, then quarantine and reject safely.

Read the guide →

Fundamentals

Disposable email addresses

Disposable email addresses are temporary inboxes. Learn why they appear in your data, how detection works and whether to block, flag or allow them.

Read the guide →

Deliverability

Bounce rate and sender reputation

Learn how hard and soft bounces and invalid addresses affect sender reputation, what verification can fix, and a simple list-hygiene routine.

Read the guide →

Fundamentals

Catch-all domains and role accounts

Catch-all domains accept mail for any address, and role accounts like info@ are shared inboxes. Learn how verifiers treat them and what to do.

Read the guide →

Free tools

Try it on your own data.

Free tool

Email verifier

Check any address in seconds. See syntax, domain, mail servers, disposable provider and role account, with the evidence behind the verdict.

Open the tool →

Free tool

DMARC checker

Type a domain to read its SPF, DMARC and MX records live. See where it sits on the DMARC ladder and what to publish next.

Open the tool →

Free tool

Email list checker

Paste a list. The analysis runs in your browser, so nothing is uploaded until you choose to verify.

Open the tool →