Or look up a domain's DNS
This leaves your browser. It goes to cloudflare-dns.com. Pregunta a Cloudflare (DNS sobre HTTPS) por los registros de correo del dominio que escribas.
How to use
What this is
Paste an email’s headers ("Show original" in Gmail, "View source" in Outlook, or the text of an .eml) and it tells you what SPF, DKIM, and DMARC say about it, plus a couple of social-engineering indicators (a Reply-To that differs from the From). It also accepts SPF/DMARC/DKIM DNS records (the output of dig, or the value as-is) to audit a domain’s CONFIGURATION. Nothing leaves your browser.
Why doesn't it recompute DMARC alignment?
Because the receiving server ALREADY computed it with data these pasted headers don't have in full (every intermediate hop, the exact organizational domain). This tool translates and explains what Authentication-Results already says with dmarc=, instead of trying to guess it worse.
Look up a domain's DNS
Optional, and only when you click: it asks Cloudflare, over DNS over HTTPS, for the domain's SPF, DMARC, MTA-STS, TLS-RPT, BIMI and, if you give its selector, DKIM key. Whatever comes back goes into the box and is audited as if you had pasted it. It also follows every SPF include and counts the lookups of the whole tree: RFC 7208's limit of 10 applies to the entire tree, and pasting only the top record doesn't show it. What goes out is the name of each record looked up, never what is in the box.
Where do I get the DNS records?
With dig txt yourdomain.com, dig txt _dmarc.yourdomain.com, or dig txt selector._domainkey.yourdomain.com — or from your DNS provider’s dashboard. Paste the whole line or just the value, quoted or not: it’s recognized either way.
