SPF is evaluated against the envelope sender
SPF publishes authorized sending systems in a TXT record. Receivers evaluate mechanisms such as ip4, a, mx and include against the connecting host.
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SPF checker
Inspect the SPF record and its recursive DNS lookup budget for a domain.
Your result will appear here.
Run the check to see structured findings, severity, evidence and next steps from the public diagnostics API.
The details
SPF is evaluated against the envelope sender
Mind the lookup budget
SPF permits at most ten DNS-querying terms during evaluation, including nested includes and redirects. Multiple SPF records at the same name cause a permanent error.
A result is a point-in-time check
DNS can vary by resolver and change over time. Verify important changes with your DNS provider and mail platform. Public DNS checks cannot see every private report or sending configuration.
Explore MailConfig ProFrequently asked questions
What does the SPF checker do?
Inspect the SPF record and its recursive DNS lookup budget for a domain.
Do I need an account?
No. This public tool is available without registration.