10IPS IP & network intelligence
Guide · Website & Domain

What is SPF and how to check it

SPF tells the world which servers are allowed to send email for your domain — a first line of defence against spammers forging your address.

Tool: SPF checker Try it now — free, no signup. Open →

What it is

SPF (Sender Policy Framework) is a single DNS TXT record listing the servers permitted to send mail as your domain. It looks like v=spf1 include:_spf.google.com ~all.

Receiving mail servers read it and check whether the sending server is on your approved list.

Why it matters

Without SPF, anyone can forge the “From” on your domain, and your legitimate mail is more likely to land in spam. SPF is also a prerequisite for getting full value from DMARC.

How to check

Enter your domain in the tool above. It finds your SPF record, checks the syntax, and flags common issues like a missing record or too many DNS lookups.

How to fix

  • Publish one TXT record starting with v=spf1 that includes every sender you use (your host, Google/Microsoft, marketing tools).
  • End with ~all (soft-fail) or -all (hard-fail) once you're confident.
  • Keep to one SPF record and under 10 DNS lookups.

FAQ

Can I have two SPF records?

No — a domain must have exactly one SPF TXT record. Merge them into a single record.

What's the difference between ~all and -all?

~all softly marks unlisted senders as suspicious; -all rejects them. Use -all once you're sure every sender is included.

Does SPF alone stop spoofing?

It helps, but pair it with DKIM and DMARC for real protection.

Related guides