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Free SPF check
Validate your SPF record: whether it exists, how strict it is and whether it stays within the 10 DNS lookups receivers allow.
3 of 3 free checks left today · No sign-up. Public DNS data only.
What SPF is and why it matters
SPF is a TXT record on your domain that lists the servers allowed to send email for it. Receiving servers compare the sending server's address with that list.
Without SPF, receivers cannot tell your servers from anyone else's. SPF is also one of the two checks DMARC relies on, so a broken SPF record weakens DMARC too.
example.com. 3600 IN TXT "v=spf1 include:_spf.google.com include:mailgun.org -all"include adds your providers' servers. -all says every other server is not allowed.
Common problems we find
No SPF record
Receivers have nothing to check the sender against.
~all or ?all
Soft fail and neutral let mail from unlisted servers through.
More than 10 DNS lookups
Each include costs lookups. Past 10, receivers treat SPF as an error.
Two SPF records
Only one v=spf1 record is allowed; with two, SPF fails.
How to fix it
- 01List every service that sends email for you and add its include.
- 02Merge everything into one record that starts with v=spf1.
- 03End with
-allonce the list is complete.
Questions
Should I use -all or ~all?
Use -all when your list is complete. With DMARC at p=reject the difference is small, but -all is the clearer signal.
More checks: DMARC · DKIM · DNSSEC · All DNS checks
Check the whole domain, not just one record
The free check covers SPF, DKIM, DMARC and MX in one go.