{"id":32,"date":"2026-09-28T12:12:51","date_gmt":"2026-09-28T09:12:51","guid":{"rendered":"https:\/\/mx1mail.com\/blog\/what-is-spf-how-does-it-work\/"},"modified":"2026-09-28T12:12:51","modified_gmt":"2026-09-28T09:12:51","slug":"what-is-spf-how-does-it-work","status":"publish","type":"post","link":"https:\/\/mx1mail.com\/blog\/en\/what-is-spf-how-does-it-work\/","title":{"rendered":"What Is SPF and How Does It Work?"},"content":{"rendered":"<p>SPF, or Sender Policy Framework, is an email authentication mechanism that publishes which servers are authorized to send mail on behalf of a domain.<\/p>\n<h2>Why is SPF used?<\/h2>\n<p>Attackers can attempt to use a company&#8217;s domain as a sender address. SPF helps receiving mail systems determine whether the connecting server is authorized.<\/p>\n<h2>Where is an SPF record stored?<\/h2>\n<p>SPF information is published as a TXT record in the domain&#8217;s DNS zone. The record can authorize IP addresses or external email services.<\/p>\n<h2>What does the receiving server do?<\/h2>\n<p>When a message arrives, the receiver queries the sender domain&#8217;s SPF record and checks whether the sending system is permitted.<\/p>\n<h2>Is SPF enough by itself?<\/h2>\n<p>No. SPF is an important layer, but DKIM and DMARC provide additional authentication and policy capabilities.<\/p>\n<h2>Common SPF mistakes<\/h2>\n<ul>\n<li>Publishing multiple SPF records for one domain<\/li>\n<li>Forgetting legitimate sending services<\/li>\n<li>Using overly broad authorization<\/li>\n<li>Ignoring DNS lookup limits<\/li>\n<\/ul>\n<p>Read our broader <a href=\"https:\/\/mx1mail.com\/blog\/en\/what-are-spf-dkim-and-dmarc\/\">SPF, DKIM and DMARC guide<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Learn how SPF works through DNS and how it helps receiving mail servers determine which systems are authorized to send email for a domain.<\/p>\n","protected":false},"author":0,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[96,101],"class_list":["post-32","post","type-post","status-publish","format-standard","hentry","category-technical-guides","tag-dns-en","tag-spf-en"],"_links":{"self":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/posts\/32","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"replies":[{"embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/comments?post=32"}],"version-history":[{"count":0,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/posts\/32\/revisions"}],"wp:attachment":[{"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/media?parent=32"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/categories?post=32"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mx1mail.com\/blog\/wp-json\/wp\/v2\/tags?post=32"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}