SPF Record Builder & Validator

Construct an SPF record mechanism by mechanism, then publish the result as a single DNS TXT record. Lints for the 10-DNS-lookup limit, length, and common mistakes.

Mechanisms

Each row is a mechanism evaluated left-to-right. include, a, mx, ptr, and exists each cost an extra DNS lookup (RFC 7208 max 10).

Default policy: -all (fail) ~all (softfail) ?all (neutral) +all (pass — dangerous)

SPF Record

v=spf1 -all

Length: 0 chars DNS lookups: 0 / 10 Mechanisms: 0

Parse / Validate Existing Record

Paste an existing SPF record (e.g. from dig +short TXT example.com) to load it into the builder.

Mechanism Reference

Mechanism	Meaning	DNS
ip4:1.2.3.4	Authorize an IPv4 address or CIDR	0
ip6:2001:db8::/32	Authorize an IPv6 address or CIDR	0
a / a:domain	A/AAAA records of domain	1
mx / mx:domain	MX hosts of domain	1
include:domain	Recursively evaluate another SPF	1+
exists:domain	Macro-expanded A lookup	1
ptr:domain	Reverse DNS — discouraged	1+
redirect=domain	Replace policy with another domain	1+

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