SPF

SPF (RFC 7208) lets a domain owner publish which hosts may send mail using that domain. It's a DNS TXT record starting with v=spf1, followed by mechanisms such as ip4:, ip6:, a, mx and include:, and ending with an 'all' qualifier: -all (fail anything not listed), ~all (softfail) or ?all (neutral).

A receiving server checks SPF against the domain in the envelope sender, the SMTP MAIL FROM address, which later appears as the Return-Path header (and optionally the HELO name). It does not check the visible From: header. Results include pass, fail, softfail, neutral, none, temperror and permerror.

SPF has practical limits: evaluating a record may trigger at most 10 DNS-querying mechanisms (include, a, mx, ptr, exists, redirect), so stacking many include: entries can cause a permerror. SPF also usually breaks when mail is forwarded, because the forwarding server isn't in the original sender's list.

Google and Yahoo require all senders to set up SPF or DKIM, and bulk senders to set up both. Without SPF, cold emails from a new outreach domain are far more likely to be rejected or sent to spam. SPF also feeds DMARC, which needs SPF or DKIM to pass with a domain aligned to your From: address.

Skrap.ai doesn't set up SPF for you; that's a DNS change at your domain host and email platform. Check your record with the free SPF checker: it follows every include and counts the 10-lookup limit. What Skrap does is on the list side: verifying your list with the free email verifier or a bulk upload so bounces don't undo the work of authenticating your domain.