SPF record generator

Pick every platform that sends mail as your domain. The lookup cost shown against each one was resolved from live DNS, not guessed — so the running total is the number receivers will actually compute.

Publishing it

Create a TXT record on the domain itself — host @ or blank, depending on your DNS provider. Not on a subdomain, and not as an SPF-type record (that record type was deprecated in 2014).

You may publish exactly one SPF record. If one already exists, merge the two by hand rather than adding a second — two records is a permerror and breaks SPF entirely.

If you are over ten lookups

The generator turns the counter red past ten because that is the point where SPF stops working. In order of preference: remove providers you no longer use, move a sender to its own subdomain (which gets its own budget), rely on DKIM instead for senders that support it, and only then consider flattening.