SPF (Sender Policy Framework)
SPF is a DNS record that lists which mail servers are allowed to send email as your domain. A definition, with a link to the full guide.
Product & Engineering · July 17, 2026 · 1 min read
SPF (Sender Policy Framework) is a DNS TXT record that publishes the list of mail servers permitted to send email on your domain's behalf. When a message arrives, the receiving server checks whether it came from a listed server.
It is one of the three core email authentication standards, alongside DKIM and DMARC. A domain may have only one SPF record, and it is limited to ten DNS lookups.
See the full guide: Full guide: how to set up SPF.
Resources in this guide
| Property | Value |
|---|---|
| Record type | DNS TXT |
| Purpose | Authorize sending servers |
| Limit | One record, ten DNS lookups |
Frequently asked questions
What does SPF do?
SPF tells receiving mail servers which servers are authorized to send as your domain, so they can reject or distrust mail from anywhere else claiming to be you.
Continue learning