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SPF Record Flattener
Collapse any domain's SPF include chain into a single flat record using only ip4: and ip6: ranges — zero DNS lookups, ready to copy.
Live DNS resolution, no account required. Monitor SPF alignment alongside DMARC.
See plans →Frequently asked questions
What is SPF flattening?
SPF flattening converts an SPF record that chains multiple
include: directives (each costing a DNS lookup) into a single record containing only ip4: and ip6:ranges. Flat records have zero DNS lookup cost and cannot exceed RFC 7208's 10-lookup limit.Why does a flat SPF record go stale?
ip4: and ip6: ranges encode specific IP addresses. When a mail service provider (Google Workspace, SendGrid, Mailchimp) adds or removes sending IPs, your flat record no longer covers their new addresses and SPF starts failing for legitimate mail. The original include: directives always reflect the current state because they are resolved at send time; flat records are frozen at the time of generation.How often should I update a flattened SPF record?
Any time a sending service updates its IP ranges, which can happen without notice. As a practical baseline, re-generate and republish your flat record every 30–90 days, or subscribe to change notifications from your major ESPs.
Does a flat SPF record improve email deliverability?
It eliminates
permerror caused by exceeding the 10-lookup limit, which would otherwise cause SPF to fail entirely. Beyond that, a correctly configured flat record is equivalent to one using include: directives — receiving servers see the same authorized IP list either way.