Free SPF Record Checker
Validate SPF syntax, count nested DNS lookups (including 'include' chains), and catch the RFC 7208 10-lookup limit before it breaks your email.
How it works
Enter a domain
We query the root TXT records and find any record starting with v=spf1.
Recursively count lookups
Every 'include:' triggers a sub-lookup. We walk the chain and tally the total.
Get a clean verdict
Mechanisms, qualifiers, lookup count, and a list of issues — color-coded by severity.
Frequently asked questions
Why does the 10-lookup limit matter?+
RFC 7208 §4.6.4: if SPF resolution exceeds 10 DNS lookups, receivers must return permerror. That means your messages get treated as if SPF failed even when the record is fine in spirit.
I have multiple SPF records — is that bad?+
Yes. RFC 7208 requires exactly one. Multiple SPF records cause receivers to permerror. Merge them into a single record.
What's the difference between -all, ~all, and ?all?+
-all = hard fail (reject), ~all = soft fail (mark suspicious), ?all = neutral (no action). Use ~all while rolling out, -all in steady state. Never use +all.
What about 'redirect=' modifiers?+
redirect= replaces the current SPF policy with another domain's. We follow it and count its lookups too.
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