SPF Record Tree Visualizer

Enter any domain to see its complete SPF include chain resolved recursively. Visualize how DNS lookups are consumed at each level.

The 10 Lookup Problem

SPF records have a hard limit of 10 DNS lookups (RFC 7208). Every include:, a:, mx:, redirect=, and exists: mechanism counts as a lookup. Nested includes count too — if your SPF includes Google Workspace, and Google's SPF includes three more domains, that's four lookups just for Google.

When you exceed 10 lookups, receiving servers return a "permerror" and SPF fails for every email you send.

How to Fix Too Many Lookups

• Remove unused services — Audit every include. If you stopped using a service, remove it.
• Replace includes with IP addresses — Use ip4: and ip6: directives instead of includes. These don't count toward the limit.
• Use SPF flattening — Services that resolve includes to IPs automatically.
• Split across subdomains — Marketing from mail.domain.com, transactional from notify.domain.com.

Scan your domain to check your current SPF lookup count.