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SPF Record Checker

An SPF record is a TXT record that lists which servers are allowed to send email for your domain. Receivers use it to detect spoofing. This checker looks up your SPF record, verifies it ends in a proper ~all or -all, and warns when you exceed the 10 DNS-lookup limit that causes a PermError.

SPF Checker, FAQ

What is an SPF record?
SPF (Sender Policy Framework) is a DNS TXT record starting with v=spf1 that declares which servers may send email for your domain. Receiving servers check it to reject forgeries.
What does ~all vs -all mean?
-all (hard fail) tells receivers to reject anything not listed; ~all (soft fail) marks it suspicious but may still accept. Avoid +all, which authorises the entire internet.
Why does SPF fail with too many lookups?
SPF allows a maximum of 10 DNS lookups (include, a, mx, ptr, exists, redirect). Beyond that, receivers return a PermError and SPF is ignored. Flatten nested includes to stay under the limit.

Want the complete picture? The Deliverability Radar scores a domain or IP out of 100 across DNS, authentication, reputation and connectivity, and emails you a branded PDF.

More free tools: DMARC Checker · DKIM Checker · MX Lookup · Reverse DNS Lookup · MTA-STS Checker · Blocklist Checker · DNS Lookup · Blocklist Checker

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