Email Header Analyzer
Paste the full raw headers of an email — typically found under "Show original" or "View source" in your mail client.
Running diagnostics…
Resolving DNS records
Free online tools to test SPF, DKIM, DMARC, MX records, DNS blacklists, reverse DNS and SMTP/STARTTLS. Run a one-click Mail Security Check, get a 0–10 score with per-record findings and download a shareable PDF report.