Free agency tools / SPF Inspector

SPF record inspector & lookup counter

SPF silently breaks once a record needs more than 10 DNS lookups. This expands every include and redirect into a tree and counts the lookups, so you can see exactly which service is spending your budget.

How it works

  1. 1Enter a domain — we fetch its SPF record.
  2. 2Every include and redirect is expanded recursively into a tree.
  3. 3We count the DNS-querying mechanisms against the RFC 7208 limit of 10 and flag where the budget goes.

Frequently asked

Why is there a 10-lookup limit?

SPF caps DNS-querying mechanisms at 10; exceed it and receivers return a permerror, effectively failing SPF.

What counts toward the limit?

include, a, mx, ptr, exists and the redirect modifier — each is one lookup, and includes bring their own nested lookups.

What happens if I'm over?

Trim or flatten includes. Consolidating providers or using an SPF-flattening service brings you back under 10.

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