Validate a domain's SPF record and catch the mistakes that hurt deliverability.
Enter a domain to check its SPF configuration.
SPF (Sender Policy Framework) is a DNS record that lists which servers are allowed to send email for your domain. Receiving servers check it to help decide whether your mail is legitimate.
Common SPF mistakes silently damage deliverability: having two SPF records, exceeding the ten DNS-lookup limit, or ending with a permissive +all. This checker analyses your record and flags each issue.
No. RFC 7208 permits exactly one SPF record per domain. Multiple v=spf1 records cause a permerror and receiving servers may ignore SPF entirely. Merge them into a single record.
SPF mechanisms that trigger DNS lookups (include, a, mx, ptr, exists, redirect) are capped at ten total. Going over the limit causes a permerror, so keep includes lean and flatten where you can.
Use -all (hard fail) for the strictest policy once you are confident every legitimate source is listed, or ~all (soft fail) while testing. Avoid ?all (neutral) and never use +all, which authorises anyone to send.
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