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SPF record checker
Look up a domain's SPF record, count the DNS lookups it costs (receivers stop at 10), and see every problem with a fix.
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Add your domain and we give you the exact SPF, DKIM, DMARC and return-path records, check them for you, and sign every message with your own domain's key. Free for 3,000 emails a month.
What SPF does
SPF is a TXT record at your domain that lists the servers allowed to send mail for it. Receivers compare the server that delivered a message with that list.
Every include:, a, mx, exists and redirect= costs a DNS lookup, and includes can contain more includes. Past 10 lookups receivers give up and SPF fails for every message, which is the most common SPF problem and the hardest to see by eye.
Go deeper: SPF, DKIM and DMARC for transactional email
Questions
What is the SPF 10 lookup limit?
RFC 7208 caps an SPF evaluation at 10 DNS lookups. include, a, mx, ptr, exists and redirect each count, including the ones inside included records. Over 10 is a permanent error and SPF fails for all of your mail.
Should my SPF record end in ~all or -all?
~all (soft fail) is the safe default: mail from unlisted servers is marked suspicious rather than rejected. Move to -all once you're sure every service that sends for you is listed. Never use +all, which lets anyone send as you.
Can I have two SPF records?
No. With more than one v=spf1 record SPF fails for everything. Merge them into one record with every include in it.
What SPF include does Groundmail use?
include:spf.groundmail.dev. When you add a domain, Groundmail shows the record with our include merged into the one you already have.