SPF Lookup
Find and validate the SPF record, expand includes, count DNS lookups (10-lookup limit) and flag syntax issues.
About the SPF Lookup
SPF (Sender Policy Framework) is the TXT record beginning with v=spf1 that lists which servers are allowed to send mail for your domain. This tool retrieves it from the authoritative name servers, parses every mechanism, recursively expands all include: and redirect= references and — most importantly — counts the DNS lookups.
The 10-lookup limit
RFC 7208 allows at most 10 DNS-querying mechanisms (include, a, mx, ptr, exists, redirect) across the whole tree. Exceed it and receivers return PermError, which most treat as “no SPF”. Because SaaS vendors nest their own includes, it is easy to break this without noticing. The include tree in the Details tab shows exactly where the lookups go.
Other checks
- Multiple SPF records (a permanent error).
+alland?allendings that authorise everyone.- Deprecated
ptrmechanisms, invalid IP ranges and unknown terms. - Includes that point at domains without an SPF record.
Use the SPF Generator to rebuild a record from vendor presets, or the raw validator to test before publishing.
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