Free tool · No account · Instant results
Free Email Deliverability Audit — 20 checks in seconds.
Paste your raw email headers or upload an .eml file and get an instant deliverability health score across authentication, DNS, sender reputation, MBP compliance, and content. Free forever.
- SPF / DKIM / DMARC
- From Alignment
- DMARC Policy Strength
- PTR / Reverse DNS
- Domain Age
- MX Record Health
- IP Blacklists (15 RBLs)
- SenderScore
- Gmail Feb 2024 Requirements
- Yahoo Requirements
- List-Unsubscribe
- One-Click Unsubscribe (RFC 8058)
- SpamAssassin Score
- Subject Spam Triggers
How to get your email headers: In Gmail, open the email → click ⋮ (More) → Show original. Copy everything from the top down to the first blank line. In Outlook, open the email → File → Properties → Internet headers.
Paste your email headers or upload an .eml file
Get your full email in your inbox, then copy the raw source. Gmail: ⋮ → Show original. Outlook: File → Properties.
Tip: Ctrl+Enter to run
One audit, one moment in time
Brain watches it every day.
Your audit is a snapshot. InboxStack Brain monitors sender reputation, ESP signals, blacklists, DMARC reports, and Google Postmaster data continuously — and traces every inbox rate drop to its root cause.