--- title: "5 Reasons Why Your Website Needs an SPF Record Flattener? | DuoCircle" description: "5 Reasons Why Your Website Needs an SPF Record Flattener?" image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/blog/email-security/5-reasons-why-your-website-needs-an-spf-record-flattener/" --- Quick Answer RFC 7208 caps SPF evaluation at 10 DNS lookups per record. Flattening replaces nested include chains with the underlying ip4 and ip6 addresses, which keeps you under the limit, prevents permerror, speeds up SPF evaluation, lowers false positives, and makes record changes easier to audit. Share [ ](https://www.linkedin.com/sharing/share-offsite/?url=undefined%2Fblog%2Femail-security%2F5-reasons-why-your-website-needs-an-spf-record-flattener%2F "Share on LinkedIn") [ ](https://twitter.com/intent/tweet?text=5%20Reasons%20Why%20Your%20Website%20Needs%20an%20SPF%20Record%20Flattener%3F&url=undefined%2Fblog%2Femail-security%2F5-reasons-why-your-website-needs-an-spf-record-flattener%2F "Share on X/Twitter") [ ](https://www.facebook.com/sharer/sharer.php?u=undefined%2Fblog%2Femail-security%2F5-reasons-why-your-website-needs-an-spf-record-flattener%2F "Share on Facebook") [ ](https://reddit.com/submit?url=undefined%2Fblog%2Femail-security%2F5-reasons-why-your-website-needs-an-spf-record-flattener%2F&title=5%20Reasons%20Why%20Your%20Website%20Needs%20an%20SPF%20Record%20Flattener%3F "Share on Reddit") [ ](mailto:?subject=5%20Reasons%20Why%20Your%20Website%20Needs%20an%20SPF%20Record%20Flattener%3F&body=Check out this article: undefined%2Fblog%2Femail-security%2F5-reasons-why-your-website-needs-an-spf-record-flattener%2F "Share via Email") ![SPF Record Flattener](https://media.mailhop.org/duocircle/images/2023/09/DMARC-generator-6872.jpg) These days, every website is on the radar of malicious actors; doesn’t matter if you own a multi-national company or a home-grown e-commerce platform. You have a website, that means you have to be cautious and driven towards **email authentication** based on SPF, [DKIM](/resources/what-is-dkim), and [DMARC](/resources/what-is-dmarc). An SPF record is a **TXT-type record** that includes all the IP addresses and mail servers that domain owners officially allow to be used for sending and receiving email messages on behalf of their organizations. [SPF records](/content/spf-records) are published on DNS, and recipients’ mail servers have to perform DNS lookups to retrieve them to conduct the validation process. However, as per [RFC7208](https://www.rfc-editor.org/info/rfc7208), there’s a maximum limit of **10 DNS lookups** per SPF record. Once the limit is reached, the SPF DNS record becomes erroneous. SPF record flattening helps take care of this problem for you. So, dig into this detailed blog on the same. We’ll touch base on everything important. ## Reasons for the SPF DNS Lookup Limit Before we talk about why every website needs an SPF record flattener, let’s quickly know **why this limit is imposed** in the first place- ### Performance The more the number of DNS lookups, the slower the processing and transmitting process, especially for busy [email servers](https://cybersecuritynews.com/hackers-attack-email-servers/). _The limit prevents the overburdening of the resources and prompts responsiveness._ ### Abuse Prevention Without this limit, hackers can flood **recipients’ mail servers** with [DNS queries](https://bunny.net/academy/dns/what-is-a-dns-and-recursive-query/), triggering Distributed Denial-of-Services or [DDoS attacks](https://gamerant.com/destiny-2-ddos-attacks-server-issues-lag-disconnects-continued/). ### Complexity Handling an arbitrary number of DNS lookups for SPF checks could lead to **overly complex** email server configurations and make it difficult to predict the processing time for incoming emails. [![How SPF works](https://media.mailhop.org/duocircle/images/2023/09/spf-permerror.jpg)](https://media.mailhop.org/duocircle/images/2023/09/spf-permerror.jpg) ## What is Flattening an SPF Record? SPF record flattening **simplifies and optimizes** [invalid SPF records](https://autospf.com/spf-validation-failed-meaning-and-troubleshooting-methods/invalid-spf-record/) by reducing the number of DNS lookups required for the authentication process. This also minimizes the likelihood of getting legitimate emails marked as spam, which is also called instances of [false positives](https://www.technologyrecord.com/article/the-danger-of-false-positives-for-security-systems). ## How Does SPF Record Flattening Work? [SPF flattening](/resources/spf-too-many-dns-lookups) works by saving you from the ‘Permerror SPF **permanent error** too many DNS lookups’, which could otherwise wreak havoc on your authentication process. An SPF flattener is a tool that **automatically condenses** the submitted record by removing mechanisms like **‘a,’ ‘mx,’ and ‘include’** to eliminate the need for additional lookups. Also, the domains earlier pointed to by the SPF mechanisms are represented solely by a string of ip4 and ip6 rules in a single SPF record. ### Example: Let’s say you submitted an SPF record with an ‘include’ mechanism for your outsourced marketing agency, which included several domains. Now, an [automatic SPF flattener](/email/spf-record-check) would resolve all these **includes and macros into a single**, flat SPF record with a list of IP addresses and mechanisms. ## 5 Compelling Reasons to Use SPF Record Flattening Services As per an [IBM report](https://www.ibm.com/reports/data-breach), phishing is the **second most common cause** of data breaches. Implementation of SPF prevents that from happening only if the record is devoid of any errors, including ‘[SPF Permerror](/content/spf-permerror)’. So, here we have enlisted 5 reasons why you should not overlook an SPF flattener. ### 1\. Avoiding DNS Lookup Limits Each DNS lookup consumes server resources, which causes delays in email transmission and delivery. _SPF flattening minimizes the requirement for SPF DNS lookups, which resolves the issue of overburdening the resources to go through a **smoother email transmission**._ ### 2\. Mitigating the SPF Record Size Limitation An SPF record can’t exceed the **limit of 255 characters**, and complex or overly fragmented records often violate this. This triggers email authentication failures and gives phishers the opportunity to [exploit reputed domains](https://siliconangle.com/2023/06/26/domain-name-system-front-center-exploits-security-policy/) to their advantages. SPF flattening services make them concise and compliant with this limitation. ### 3\. Boosting Email Deliverability _Some email servers find it challenging and resource-exhausting to interpret complex or nested SPF TXT records_. SPF flattening streamlines the SPF record, making it easier for receiving servers to process and **reduce the risk** of legitimate emails being marked as spam or rejected due to SPF record complexity. ### 4\. Reducing Risks of Misconfigurations Handling several SPF records [leads to misconfigurations](https://blog.detectify.com/industry-insights/misconfigured-email-servers/), including conflicting rules or omitted senders. An SPF flattening tool reduces the instances of errors by **compressing all authorized sources** into a single, comprehensive, inclusive, yet simplified record that takes care of misconfigurations. ### 5\. Maintaining Consistency [![](https://media.mailhop.org/duocircle/images/2023/09/spf-permerror-7934.jpg)](https://media.mailhop.org/duocircle/images/2023/09/spf-permerror-7934.jpg) The existence of [multiple SPF records](https://www.courier.com/guides/multiple-spf-records/) makes it challenging to maintain uniformity across all of them. Varying instructions and the utility of mechanisms cause troubles at receivers’ ends, prompting validation issues like false positives. SPF record flattening eliminates the need to make updates to multiple records, which consequently leaves **no room for varied instructions** for recipients’ mailboxes. ## How to Know if Your SPF Record Has Exceeded the SPF Lookup Limit? There are a few ways to figure out how far before your SPF record hits the [SPF lookup limit](/what-is-spf-lookup-limit-and-how-to-fix-it) and **becomes invalid**. ### Review Your SPF Record Look for the **‘include’ and ‘a’ mechanisms** as they require DNS lookups. Note all these mechanisms. ### Count DNS Lookup Mechanisms _Count how many DNS lookup mechanisms are there in your SPF record._ Each instance of ‘**include**’ or ‘**a**’ mechanism count towards one lookup. So, if there are 2 ‘include’ mechanisms and 1 ‘a’ mechanism, then it counts to 3 [DNS lookups](https://www.techopedia.com/definition/29029/dns-lookup). ### Check Third-Party Services If your SPF record has included sending sources of [third-party vendors](https://panorays.com/blog/what-is-a-third-party-vendor/), then they would also count towards the lookup limit. For example, if you’re including a service like Google Workspace (G Suite), it **will consume a DNS lookup**. ### Consider Other Mechanisms _Mechanisms like ‘mx’ and ‘ip4’ aren’t counted towards the limit, but they contribute to make your SPF record **lengthy**, potentially triggering issues._ ### Use an SPF Lookup Tool An [SPF](/content/sender-policy-framework) lookup tool highlights all the existing errors in the queried domain’s record. It cross-checks your record against a number of elements, including the **DNS lookup count**. ### Consult a Specialist [DuoCircle](/) is the platform that resolves all your email authentication issues and **fixing the Permerror** is no big deal for us. We use automatic tools to condense your SPF record to get rid of redundant and unnecessary mechanisms and [IP addresses](/email-services/what-is-ip-reputation-and-why-it-matters-for-email-campaigns/), eliminating or reducing the need for DNS lookups. We offer digital solutions against [email-based phishing attacks](/email-hosting/the-top-three-email-based-threats-and-how-to-avoid-them/) and ensure every IT-driven business owner lives with a **head-high reputation**. [Get in touch](/contact) with us for SPF, DKIM, and DMARC implementation and monitoring. ## Topics email securitySecurityTrendsUpdates ![Brad Slavin](https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg) Brad Slavin General Manager General Manager at DuoCircle. Product strategy and commercial lead across the email security portfolio. ## Secure your email infrastructure Protect, authenticate, and deliver. Contact our team to find the right solution. [Contact Sales](/contact/) [Explore Products](/products/) ## Related Articles [ Email Security 6m Decoding Canonicalization: The Reason Behind DKIM Signature Verification Failures May 2, 2024 ](/blog/email-security/canonicalization-reason-behind-dkim-signature-verification-failures/)[ Email Security 7m Using Email Security Tools Such as Secure Email Gateways and End-To-End Encryption to Protect Email Content and Attachments Mar 9, 2023 ](/blog/email-security/ensure-confidentiality-of-your-emails-with-secure-email-gateways-and-end-to-end-encryption/)[ Email Security 7m 10 Crucial Tips that Will Help You Avoid Spam Filters and Send Better Emails Feb 14, 2023 ](/blog/email-security/10-crucial-tips-that-will-help-you-avoid-spam-filters-and-send-better-emails/)[ Email Security 3m Best Ways to Secure Emails in 2024 Apr 26, 2024 ](/blog/email-security/best-ways-to-secure-emails-in-2024/) ```json {"@context":"https://schema.org","@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. 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