Free Tool · SPF
SPF Survey
Expand a domain's SPF record, walk every include, and count it against the 10 DNS-lookup limit that breaks SPF.
Free · no signup · checks public DNS only ·
What the SPF Survey checks
SPF (Sender Policy Framework) is a DNS TXT record that lists which servers may send email for your domain. Receiving servers read it to help decide whether a message is genuine or spoofed.
The catch: SPF has a hard limit of 10 DNS lookups. Every include, a, mx, ptr, exists and redirect term — and the ones inside every record it points to — counts toward that limit. Go over 10 and strict receivers return a permerror, which can make legitimate mail fail SPF and break DMARC alignment.
This survey resolves your record, follows every include recursively, and totals the lookups so you can see exactly where they go.
Frequently asked questions
What counts as a DNS lookup in SPF?+
Each include, a, mx, ptr, exists and redirect mechanism costs one lookup — recursively, through every record they reference. ip4 and ip6 mechanisms are free.
What happens if I exceed 10 lookups?+
Strict receivers return a permerror and treat SPF as failed, even for legitimate senders. That hurts deliverability and can break DMARC alignment.
How do I fix too many lookups?+
Remove unused includes, or flatten your SPF into static IP ranges. CertaDNS Dynamic SPF keeps your record flattened and up to date automatically.
Is this tool free?+
Yes — it only reads public DNS records and needs no signup.
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