⚕️ Your emails deserve the inbox

Find out why your email lands in spam

InboxDoctor audits your domain's SPF, DKIM, DMARC and MX records in seconds — then hands you a graded report with the exact DNS fixes to paste in. No mail sent, no signup to try.

Or see a sample report for a failing domain →
1 in 6legit emails never reach the inbox
Feb 2024Gmail & Yahoo made DMARC mandatory
<10sto audit any domain
The problem

Email authentication is invisible — until it costs you

One misconfigured DNS record silently sends your invoices, password resets and outreach to spam. Most teams don't find out until a customer says "I never got it." Since Gmail and Yahoo's 2024 rules, a missing DMARC record can get bulk mail blocked outright.

🛡️

SPF, checked properly

We follow every include: and flag the RFC 10-lookup limit that silently breaks SPF — the check other free tools skip.

🔑

DKIM discovery

We probe 25+ known selectors across Google, Microsoft, SendGrid, Mailchimp and more to confirm your mail is actually signed.

📊

DMARC enforcement

Not just "present" — we grade whether you're monitoring or truly blocking spoofers, and whether reports are flowing.

📄

A report you can send

A clean, branded HTML report with a letter grade and copy-paste fixes — hand it to a client or your own IT team.

How it works

From "why am I in spam?" to fixed in three steps

Scan

Enter your domain. We query public DNS only — nothing is sent to your mailbox and no credentials are needed.

Grade

Get an A–F score across MX, SPF, DKIM, DMARC and advanced protections, with plain-English explanations.

Fix

Copy the exact DNS records we generate into your provider. Re-scan to confirm you've hit an A.

Pricing

Start free. Pay when you need to monitor.

The one-off audit is free forever. Paid plans keep watching your records and alert you the moment something drifts.

Free scan

$0
For a quick one-off check
  • Full SPF / DKIM / DMARC / MX audit
  • Letter grade & score
  • Copy-paste DNS fixes
  • Shareable HTML report
  • CLI: npx inboxdoctor
Try it now
MOST POPULAR

Pro monitoring

$12/domain/mo
For founders & small teams
  • Everything in Free
  • Daily automated re-scans
  • Email/Slack alerts on any drift
  • DMARC aggregate-report parsing
  • Uptime-style status history
Start 14-day trial

Agency

$99/mo
For agencies & MSPs
  • Up to 50 client domains
  • White-label branded reports
  • Bulk scan & CSV export
  • Team seats & client sharing
  • API & CI integration
Book a demo
FAQ

Questions, answered

Do you send test emails or need access to my mailbox?

No. InboxDoctor reads only public DNS records (the same data any receiving mail server sees). Nothing is sent to your inbox and we never ask for credentials.

How is this different from free tools like MXToolbox?

We combine SPF, DKIM, DMARC, MX and advanced records into a single graded report with prioritised, copy-paste fixes — and we recursively resolve SPF includes to catch the 10-lookup limit that silently breaks authentication. Pro also monitors continuously instead of a one-time check.

Can I run it in CI/CD?

Yes. The CLI supports --fail-under 80, which exits non-zero when your score drops below a threshold — perfect for catching DNS regressions before they ship.

Why does email authentication matter now?

Since February 2024, Google and Yahoo require SPF, DKIM and DMARC for anyone sending bulk email. Get it wrong and your messages are throttled, spam-foldered, or rejected outright.

Is your domain inbox-ready?

Run a free scan in under ten seconds. No signup required.

See a real report →