SPF DNS lookup counter
Count how many of the 10 permitted DNS lookups a domain's SPF record uses, with the full include tree.
Free, instant, no signup. Results include SPF, DKIM and DMARC together.
Why 10 lookups matters
RFC 7208 section 4.6.4 limits SPF evaluation to 10 DNS-querying mechanisms, counted across the whole include tree. Exceeding it produces permerror, which most receivers treat as SPF fail. Because each vendor include may itself contain several includes, a record that looks short (include:_spf.google.com include:sendgrid.net include:spf.protection.outlook.com …) often uses 8 to 12 lookups.
This tool shows the resolved tree so you can see which include costs the most, and whether any include is void (points at a domain with no SPF record), which has its own limit of 2.
Read the guide: fixing SPF too many DNS lookups.
Get told when it changes
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Public checks run in the last few days. Every report is measured live from DNS when it is opened.