SPF Validator
Look up the SPF record of a domain, or paste a record, and see whether it is valid. The tool follows every include and redirect and counts the DNS lookups across the whole chain.
The check follows include and redirect records through DNS and stops at six levels. DNS answers can be cached, so a change you just made may take time to appear.
What is SPF Validator?
An SPF validator checks that a record follows the syntax in RFC 7208 and that it will not cause a permanent error at the receiving server. This tool checks the version tag, each mechanism and modifier, IP address and range formats, and warnings such as the deprecated ptr mechanism or terms placed after all. It follows include and redirect records through DNS and counts the lookups across the whole chain, because SPF allows at most 10 and receivers treat more as an error. It also detects duplicate SPF records, missing records and include loops. DNS answers can be cached, so a recent change may take time to appear.
Why use this tool?
- Check a domain's live SPF record, or paste a record you are drafting.
- Follows include and redirect records through DNS, up to six levels, and shows the chain.
- Counts DNS lookups across the whole chain against the limit of 10.
- Reports duplicate records, missing records, invalid values, include loops and risky settings.
How to use SPF Validator
- Step 1. Choose Check a domain and enter your domain, or choose Paste a record and paste the value.
- Step 2. In paste mode, keep the option on to follow includes through DNS, or turn it off to check only the pasted record.
- Step 3. Select Validate SPF.
- Step 4. Read the verdict, the lookup count and the chain, then fix any problems or warnings listed.
Common use cases
Important notes
- The check follows include and redirect terms. Each a, mx, exists and ptr term counts as one lookup, but the extra address lookups that a and mx make are not counted separately.
- This tool checks the record. It does not test whether a particular IP address would pass.
- DNS answers can be cached, so a change you made recently may take time to appear.
- A ptr term is deprecated, and terms placed after all have no effect.
More DNS & Website Tools
SPF Validator FAQ
Why does my SPF record fail with too many DNS lookups?
SPF allows 10 lookups across the whole chain, and each include can add more of its own. Remove services you no longer use, or replace includes with fixed ip4 and ip6 ranges where the addresses are stable.
What does a permanent error mean?
The receiver treats the SPF record as broken, such as for two records or too many lookups, so SPF cannot pass.
Why does the tool say my domain has no SPF record?
No TXT record starting with v=spf1 was found at that name. Check the domain, and remember that each subdomain that sends mail may need its own record.
Can I check a record that is not published yet?
Yes. Use Paste a record. The tool can still follow its includes through DNS.