--- title: "What is a TXT SPF record and why is it important? | AutoSPF" description: "Per RFC 7208, SPF evaluation is capped at 10 DNS mechanism lookups and 2 void lookups per check." image: "https://autospf.com/og/blog/what-is-a-txt-spf-record-and-why-is-it-important.png" canonical: "https://autospf.com/blog/what-is-a-txt-spf-record-and-why-is-it-important/" --- Quick Answer SPF stands for Sender Policy Framework - an email authentication protocol that allows only the emails sent by authorized people to get delivered to the recipient’s inbox. Deploying SPF, DKIM, and DMARC prevents your organization from email-based phishing, spoofing, and BEC attacks. Share [ ](https://www.linkedin.com/sharing/share-offsite/?url=https%3A%2F%2Fautospf.com%2Fblog%2Fwhat-is-a-txt-spf-record-and-why-is-it-important%2F "Share on LinkedIn") [ ](https://twitter.com/intent/tweet?text=What%20is%20a%20TXT%20SPF%20record%20and%20why%20is%20it%20important%3F&url=https%3A%2F%2Fautospf.com%2Fblog%2Fwhat-is-a-txt-spf-record-and-why-is-it-important%2F "Share on X/Twitter") [ ](https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fautospf.com%2Fblog%2Fwhat-is-a-txt-spf-record-and-why-is-it-important%2F "Share on Facebook") [ ](https://reddit.com/submit?url=https%3A%2F%2Fautospf.com%2Fblog%2Fwhat-is-a-txt-spf-record-and-why-is-it-important%2F&title=What%20is%20a%20TXT%20SPF%20record%20and%20why%20is%20it%20important%3F "Share on Reddit") [ ](mailto:?subject=What%20is%20a%20TXT%20SPF%20record%20and%20why%20is%20it%20important%3F&body=Check out this article: https%3A%2F%2Fautospf.com%2Fblog%2Fwhat-is-a-txt-spf-record-and-why-is-it-important%2F "Share via Email") ![TXT SPF record](https://media.mailhop.org/autospf/images/2025/11/spf-flattening-3696.jpg) SubscribeShare _Per [RFC 7208](https://datatracker.ietf.org/doc/html/rfc7208), SPF evaluation is capped at 10 DNS mechanism lookups and 2 void lookups per check - exceeding either limit produces a `PermError` that fails authentication for every message from the domain._ SPF stands for Sender Policy Framework - an email authentication protocol that allows only the emails sent by authorized people to get delivered to the recipient’s inbox. Deploying SPF, [DKIM](/10-reasons-for-regular-spf-record-checks-in-cybersecurity/dkim-record-check/), and [DMARC](https://dmarcreport.com/) prevents your organization from [email-based phishing](https://www.bleepingcomputer.com/news/security/why-attackers-are-moving-beyond-email-based-phishing-attacks/), spoofing, and [BEC attacks](https://www.cybersecuritydive.com/news/fbi-internet-crime-bec-scams-investment-fraud-losses/746181/). Now, an SPF record is a TXT (text) record on which the entire process of email authentication via SPF relies. It includes a list of IP addresses and [mail servers](https://www.activecampaign.com/glossary/mail-server) officially authorized to send emails from your domain. You think of an [SPF record](/spf-record-checker/create-spf-record/) as a guest list to an invite-only party; if a sending source is not on the list (the SPF record), the door attendant (the recipient’s server) will mark their emails as spam or reject them. A TXT SPF record specifies which mail servers are authorized to send emails for your domain, and [automated SPF flattening](/) simplifies and optimizes this record to ensure reliable email delivery and prevent spoofing. ![check an SPF record ](https://media.mailhop.org/autospf/images/2025/11/spf-permerror-8977.jpg) ## How does a mail server check an SPF record? When a mail server checks an SPF record, it follows a simple process: 1. Server One sends an email. Its IP address is 192.0.2.0, and the email uses [email@returnpath.com](mailto:email@returnpath.com) as the [return-path](https://emaillabs.io/en/what-is-return-path/). (The return-path is not the same as the “from” address. It’s mainly used to handle bounced emails.) 2. _The receiving mail server (Server Two) looks at the domain in the return-path and searches for its SPF record_. 3. If Server Two finds the SPF record, it checks whether Server One’s IP address is listed there as an autIf the IP address is found, the [SPF check](/spf-record-tester/mimecast-spf-check/) passes, and the email is accepted. 4. If it’s not listed, the SPF check fails, and the email may be rejected or sent to the [spam folder](https://cybernews.com/news/microsofts-breach-notification-emails-end-up-in-spam-folder/). ![spam folder ](https://media.mailhop.org/autospf/images/2025/11/spf-record-tester-5897.jpg) ## SPF record syntax General example of an SPF record- v=spf1 mechanism1 mechanism2 … mechanismN qualifier Let’s break down the synatx in simple terms: - v=spf1: This shows the version of [SPF](/blog/what-is-spf-email-a-guide-to-sender-validation-technology/) being used (it’s always spf1). - Mechanisms: These define which mail servers are allowed. Common ones are: - IP4: allows an IPv4 address (e.g., ip4:192.0.2.0/24) - IP6: allows an IPv6 address - include: allows another domain’s SPF record to be used (e.g., include:\_spf.google.com) - a: allows the domain’s A record IP - mx: allows the domain’s [MX record](https://en.wikipedia.org/wiki/MX%5Frecord) IPs - all: matches everything (usually at the end) - Qualifiers: These decide what happens if an IP matches or not: - \+ (pass): allowed -, (fail): not allowed - \~ (soft fail): probably not allowed, but not strictly blocked - ? (neutral): no specific policy ![ SPF record ](https://media.mailhop.org/autospf/images/2025/11/spf-validator-6307.jpg) ### Example of a complete SPF record ``` v=spf1 ip4:192.0.2.0/24 include:_spf.google.com -all ``` This example indicates that- - Emails can be sent from IPs in 192.0.2.0/24 or from Google’s mail servers. - All others (-all) are not allowed to send emails using this domain. ![Domain protection tips](https://media.mailhop.org/autospf/images/2025/11/spf-record-5511.jpg) ## Why Is SPF records Important? An SPF record is important because it helps protect your domain from being used by spammers or hackers. It tells receiving mail servers which servers are allowed to send emails on your behalf. When someone sends an email using your domain, the receiving server checks the SPF record to confirm if it is genuine. If the email comes from an unauthorized source, it is [marked as spam](https://pressgazette.co.uk/publishers/digital-journalism/facebook-spam-posts-independent-small-news-publishers/) or rejected. This reduces the chances of [phishing and spoofing](https://www.msspalert.com/brief/novel-usps-spoofing-phishing-attack-relies-on-malicious-pdfs) attacks. Having an SPF record also improves your [email deliverability](/blog/optimizing-email-deliverability-strategies-for-success/) and helps build trust with your recipients. ## Topics [ DKIM ](/tags/dkim/)[ DMARC ](/tags/dmarc/)[ SPF ](/tags/spf/)[ SPF Flattening ](/tags/spf-flattening/)[ SPF record ](/tags/spf-record/) ![Brad Slavin](https://media.mailhop.org/autospf/images/authors/brad-slavin.jpg) [ Brad Slavin ](/authors/brad-slavin/) General Manager Founder and General Manager of DuoCircle. Product strategy and commercial lead for AutoSPF's 2,000+ customer base. [LinkedIn Profile →](https://www.linkedin.com/in/bradslavin) ## Ready to get started? Try AutoSPF free — no credit card required. [ Book a Demo ](/book-a-demo/) ## Related Articles [ Foundational 12m From Zero to Secure: Creating an SPF Record for Your Domain Mar 11, 2026 ](/blog/from-zero-to-secure-creating-spf-record-for-your-domain/)[ Foundational 14m How To Create And Check Your Domain SPF Record Online Easily Sep 2, 2025 ](/blog/how-to-create-and-check-domain-spf-record-online-easily/)[ Foundational 16m SPF Protocol Explained: Boosting Your Email Deliverability And Security Oct 28, 2025 ](/blog/spf-protocol-explained-boosting-your-email-deliverability-and-security/)[ Foundational 8m SPF Record Examples: Copy-Paste Records for Google, Microsoft 365, SendGrid & More (2026) Mar 24, 2026 ](/blog/spf-record-examples-copy-paste-for-google-microsoft-sendgrid-2026/) ```json {"@context":"https://schema.org","@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com","logo":{"@type":"ImageObject","url":"https://autospf.com/images/autospf-logo.png"},"description":"Automatic SPF flattening and email authentication management. 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Resolve SPF lookup limits, flatten SPF records, and maintain email deliverability across all your domains.","parentOrganization":{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138883901","name":"DuoCircle LLC","url":"https://www.duocircle.com","sameAs":["https://www.wikidata.org/wiki/Q138883901","https://www.crunchbase.com/organization/duocircle-llc","https://www.linkedin.com/company/duocircle","https://github.com/duocircle"],"subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]}}} ``` ```json {"@context":"https://schema.org","@type":"BlogPosting","headline":"What is a TXT SPF record and why is it important?","description":"Per RFC 7208, SPF evaluation is capped at 10 DNS mechanism lookups and 2 void lookups per check.","url":"https://autospf.com/blog/what-is-a-txt-spf-record-and-why-is-it-important/","datePublished":"2025-11-04T20:18:55.000Z","dateModified":"2026-04-18T02:36:41.000Z","dateCreated":"2025-11-04T20:18:55.000Z","author":{"@type":"Person","@id":"https://autospf.com/authors/brad-slavin/#person","name":"Brad Slavin","url":"https://autospf.com/authors/brad-slavin/","jobTitle":"General Manager","description":"Brad Slavin is the founder and General Manager of DuoCircle, the company behind AutoSPF, DMARC Report, Phish Protection, and Mailhop. 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