SPF Limit Tester
Walk SPF include chains and check the RFC 7208 10 DNS lookup and 2 void lookup limits before they break deliverability.
Try:
How the 10-lookup limit works
Each include, a, mx, ptr, exists, and redirect costs one lookup. Nested includes add up. Cross 10 and receivers return permerror.
- ip4, ip6, and all are free
- redirect is ignored when all is present
- Void answers (NXDOMAIN / empty) are capped at 2
How to fix too many lookups
- Drop includes for services you no longer send through
- Replace deep include chains with ip4/ip6 ranges when vendors publish them
- Avoid ptr and exists unless you truly need them
FAQ
Short, practical answers to common questions.