SPF Record Checker
Free SPF record checker. Validate your SPF syntax and recursively count DNS lookups against the 10-lookup limit that silently breaks SPF. Instant, no login.
About the SPF Record Checker
Use this free SPF record checker to validate your domain's SPF record and, crucially, to count how many DNS lookups it triggers. SPF is limited to 10 DNS lookups by RFC 7208 - every include, a, mx and redirect mechanism counts, including the ones nested inside your includes. Go over 10 and SPF returns a PermError, which means it silently fails at most receivers even though the record looks correct at a glance.
Enter your domain above and the checker recursively expands every include, shows exactly which mechanisms consume your lookups, flags dangerous settings like +all, and confirms whether your record terminates safely with ~all or -all.
Frequently asked questions
What is the SPF 10 lookup limit?
SPF allows a maximum of 10 DNS lookups per RFC 7208. Every include, a, mx, ptr, exists and redirect mechanism consumes one, counted recursively through nested includes. Exceeding 10 causes a PermError and SPF fails at most receivers.
Why does my SPF record fail even though it looks correct?
The most common cause is exceeding the 10 DNS lookup limit through nested includes. The record can look fine while quietly returning PermError. This checker counts the lookups recursively so you can see the real total.
Can I have two SPF records?
No. A domain must have exactly one SPF record. Two or more is invalid per RFC 7208 and causes SPF to fail. Merge them into a single record.
Did this check reveal a problem?
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