SPF record checker

Read a domain's SPF record, follow every include, and count the lookups it really costs.

What an SPF record does

SPF is a TXT record on your domain listing the servers allowed to send mail with your domain in the envelope sender. A receiver compares the connecting IP against that list and applies whatever the record's final all mechanism says: -all fails everything unlisted, ~all softfails it, and ?all and +all provide no protection at all. +all authorises the entire internet to send as you.

RFC 7208 allows a maximum of ten DNS-querying mechanisms (include, a, mx, ptr, exists and redirect), counted across every nested include, not just your own record. Add one more ESP and the whole record turns into a permerror, SPF stops passing, and under the current Gmail, Yahoo and Microsoft enforcement rules your mail starts bouncing even though the record still looks fine. This checker resolves the full chain so you can see the real total.

On a paid plan, the sending routes check gives each include a keep, review or remove verdict from 90 days of the domain's own report history.

The senders your DNS cannot name

A DNS lookup shows the record receivers read on the next message. The reports receivers send go further: they name each host that sent under your domain and whether its mail passed. Paid plans email you the day a report first names a new sender failing. One Monday email covers 5 domains on Pro, $19 a month.

Start watching your senders

No card · 12+ months of history · The free plan does not expire

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