What are SPF and DMARC?
Quick answerSPF is a DNS TXT record listing the servers allowed to send email for your domain. DMARC is a TXT record at _dmarc.yourdomain that tells receivers what to do when a message fails SPF or DKIM checks (none, quarantine or reject) and where to send reports. Together they reduce spoofing and improve deliverability.
What the checker tests
- MX: the domain can receive mail
- SPF: exactly one
v=spf1record, ending in~allor-all(never+all) - DMARC: a
v=DMARC1record, and whether its policy actually protects you
A safe rollout plan
- Publish SPF listing every service that sends as you (email provider, newsletter tool, CRM).
- Enable DKIM signing in each of those services.
- Publish DMARC with
p=noneand a report address. Read the reports for a few weeks. - Move to
p=quarantine, thenp=reject, once legitimate mail passes.
Frequent mistakes
- Two SPF records (merge them into one).
- More than 10 DNS lookups inside SPF includes, which makes SPF fail.
- DMARC stuck at
p=noneforever, so it reports but doesn't protect.
Many large mailbox providers now expect bulk senders to have SPF, DKIM and DMARC in place, so it's worth fixing even for small businesses.
Spf dmarc checker FAQ
Is this spf dmarc checker free?
Yes, unlimited and free with no sign-up. Queries go from your browser to public DNS-over-HTTPS resolvers (Cloudflare and Google).
Why do two resolvers show different results?
DNS answers are cached for the record's TTL. Right after a change, some resolvers still serve the old value. Wait for the TTL to expire and check again.
Can I look up a subdomain?
Yes. Type the full name, for example mail.example.com or _dmarc.example.com.