DNS email hygiene tool

SPF Checker

Validate SPF records, follow include/redirect chains, count DNS lookups, and get actionable hardening advice before delivery failures happen.

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Recursive include/redirect analysis DNS lookup budget tracking Best-practice risk checks

Domain quickstart

What You Can Check

Validate your SPF setup before mailbox providers reject or flag outbound messages.

Inspect include and redirect chains recursively
Track DNS lookup budget against SPF limits
Detect syntax, duplicate SPF, and recursion loop risks

If SPF Fails

Broken SPF can reduce deliverability and open abuse paths that harm your sending reputation.

Legitimate emails may land in spam or get blocked
Forwarders and third-party senders may fail alignment
Too many lookups can trigger permanent SPF errors

When SPF Is Clean

A well-maintained SPF record supports trusted delivery and simplifies incident response.

Mail servers can verify authorized senders faster
Lower spoofing risk for your visible domain identity
Stronger foundation for DMARC policy enforcement

Examples, Do's and Don'ts

Example Patterns

v=spf1 ip4:203.0.113.10 include:_spf.google.com -all
v=spf1 mx include:mail.vendor.example ~all
One SPF TXT record per host/domain, not multiple SPF records

Do

Keep includes current and remove unused senders
Stay under SPF DNS lookup limits
Retest after DNS or provider changes

Don't

Publish multiple SPF records for the same domain
Use broad +all authorization in production
Assume old includes still point to active providers