SPF Checker
An SPF checker validates your domain's Sender Policy Framework record — the DNS TXT record that tells inbox providers which servers may send mail as you. This free tool fetches your SPF record, counts its DNS lookups against the 10-lookup limit, and flags the syntax errors that silently break authentication.
Recursive lookup counting · multiple-record detection · RFC 7208
Frequently asked questions
What is an SPF record?
SPF (Sender Policy Framework) is a DNS TXT record that lists which mail servers are allowed to send email using your domain. Receiving servers check it to help decide whether a message is legitimate or spoofed.
How many DNS lookups can an SPF record have?
RFC 7208 caps SPF at 10 DNS-querying mechanisms (include, a, mx, ptr, exists, redirect). Go over 10 and conformant receivers return a permerror, so your SPF effectively fails. This tool counts your lookups recursively, including nested includes.
How do I fix "too many DNS lookups" in SPF?
Flatten or remove unused include: mechanisms, drop redundant a/mx terms, and consolidate providers. Aim for 8 or fewer to leave headroom. Some providers offer SPF flattening if you cannot get under the limit otherwise.
Can I have more than one SPF record?
No. A domain must have exactly one v=spf1 TXT record. Two or more is invalid and causes SPF to fail — merge them into a single record.
Does SPF alone stop spoofing?
No. SPF authorises sending servers but does not protect the visible From address. Pair it with DKIM and a DMARC policy of quarantine or reject to actually block spoofing.