# What Is SPF?

> SPF (Sender Policy Framework) is a DNS record listing the mail servers authorized to send email for a domain. Receiving servers check it to detect forged sender addresses, making SPF a first line of defense against domain spoofing and phishing.

*Source: https://www.whisper.security/glossary/spf*
*Published: 2026-06-22*
*Last updated: 2026-06-22*

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## Where this shows up

See it in a live investigation: [Grade DNS & email posture](/products/intelligence/use-cases/dns-email-security).

Go hands-on with [the DNS & email recipes](/docs/recipes/dns-email).