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SPF Record Builder & Lookup Validator

Add each sender your domain uses, and this builds a valid SPF record for you, with a live lookup-count meter so you catch the RFC 7208 10-lookup limit before receivers start returning permerror.

📖 Guide: How SPF records work

Last updated: August 29, 2026

Generated record
v=spf1 -all
Top-level mechanisms in this record0 / 10

This counts only what you've typed here. An include: to a third party (e.g. your email provider) almost always adds more lookups of its own, so use "Validate via live DNS" below for the real total.

Which mechanisms count toward the 10-lookup limit?
include / a / mx / ptr / exists / redirect1 DNS lookup each. include and redirect also add every lookup used inside the record they point to
ip4 / ip60: these are literal addresses, no lookup needed
all0: not a lookup, just the default action for anything unmatched

RFC 7208 hard-caps compliant SPF evaluation at 10 lookups. Go over it and mailbox providers are required to treat the entire record as a permerror, so your SPF protection stops working completely, not just for the sender that pushed it over.