SPF Recursive Lookup Counter

Counts SPF DNS lookups per RFC 7208: 1 for each include:, a, mx, ptr, exists, and redirect=. Includes are expanded recursively. PTR is deprecated but still counted if present.

How counting works

Each of these counts as one lookup: include:, a, mx, ptr, exists:, redirect=.
For an include:target, the “lookups caused by this include” = 1 (the include itself) + lookups inside target’s SPF.
ip4:, ip6:, all, and exp= do not count.
We use DNS-over-HTTPS to resolve SPF from the browser. If a provider blocks DoH or CORS, try again later.