Show HN: MXValidation – Send an email and get an authentication and DNS report

Test your email authentication, spam signals, DNS configuration and technical deliverability. Get a clear score, identify problems and learn how to fix them.

3 guest tests or 20 with a verified free account per rolling 24 hours. See limits.

Use a test copy without confidential information. Guest reports are kept for 14 days. Privacy policy.

Demo report - illustrative results, not a real email test.

The sending IP is not authorized by the SPF policy. Publish one valid SPF record for the evaluated identity and include every authorized sending service.

Use the message and sending platform you want to check.

Copy the personal address above. Each address accepts one test message.

Send a test copy using your usual sending configuration.

Choose Check Your Score. The report updates as the analyses finish.

Authentication, sending infrastructure and the message itself - with unavailable checks clearly marked Unknown.

Understand whether the sending service and message identity are authenticated and aligned.

Review spam-rule contributions and the identity and blocklist signals of the sending IP.

Find structural and delivery details that can affect handling and safe rendering.

Link destinations are not opened. Domain blocklist scanning and provider inbox-placement tests are not part of these ten checks. Read what each check measures.

Diagnose email configuration, authentication and deliverability problems with our free online tools.

Check who can send for your domain and how your brand is verified.

Read your published sender policy, understand its mechanisms and find syntax or lookup-budget risks.

Check the public key behind a DKIM selector and see whether it is usable, revoked or malformed.

Understand the policy receivers find for your domain and where authentication reports are requested.

Review your BIMI record and logo prerequisites without assuming that every inbox will display your brand.

Review receiving mail servers and the policies that protect email in transit.

Look up your domain’s mail servers, review MX priorities and identify DNS configuration issues.

Check both halves of MTA-STS: DNS discovery and the HTTPS policy that protects receiving mail.

See whether your domain requests reports about inbound SMTP TLS negotiation and policy failures.

Inspect a saved message or investigate a sending IP.

Read a saved email, inspect its headers and download individual attachments locally.

Look up a sending IPv4 in public DNS blocklists and distinguish a listing from an unavailable query.

Your report uses a weighted score out of 10. The equivalent 0–100 scale below shows the same color thresholds: 5/10 = 50/100 and 8/10 = 80/100.

Start with failed authentication and other flagged issues. Unavailable checks can also lower the score.

Some checks earned points. Work through the failures and warnings before your next send.

More of the weighted checks passed. Review individual warnings even when the overall score is high.

Your score reflects technical email configuration and spam-related signals. It does not guarantee inbox placement with Gmail, Outlook or other providers. Missing and unavailable checks earn no points. How the score is calculated.

Copy your unique test address, send your email to it from the platform you use, then choose Check Your Score. We analyze authentication, SpamAssassin signals, sending-IP reputation, DNS and message structure. This diagnoses technical risks; it does not test placement in Gmail, Outlook or other recipient inboxes.

Yes. Guests can view 3 tests per rolling 24 hours. A verified free account has a default allowance of 20 tests in that period; individual account limits may differ. The standalone DNS tools and local EML viewer do not consume this email-test allowance and have separate abuse-prevention limits.

SPF specifies which sending services may use an envelope-sender domain. DKIM signs a message so receivers can verify its signing domain and integrity. DMARC checks alignment with the visible From domain and publishes a policy for authentication failures.

No. Inbox placement depends on additional factors, including sender reputation, recipient engagement and provider-specific filtering. The score summarizes the technical evidence available in this test.

A new test address accepts one message for 24 hours. Guest report details are retained for 14 days after receipt. Account-owned history and database results have no automatic expiry and remain until you delete the test or account. Original SMTP spool files have a separate retention period of approximately 30 days after successful synchronization; queued messages may be retained longer. A minimal used-address record is kept to prevent reuse.

Find authentication issues, spam signals and technical problems before they affect your email campaigns.