SPF Record Tester Explained: How To Ensure
Your Domain’s SPF Record Is Correct


The Sender Policy Framework (SPF) serves as a crucial component of email authentication, designed to thwart spammers and phishers from impersonating your domain in their communications. A prevalent challenge that domain owners encounter is the incorrect configuration of SPF records, particularly when managing various email services. This detailed guide will provide insights into utilizing an SPF record testing tool, underscore the significance of accurate SPF setup, and address typical errors, such as the presence of multiple SPF records, which can jeopardize the deliverability of emails from your domain.


What is an SPF Record?


An SPF record functions as a specific kind of DNS TXT record that enumerates the email servers permitted to send messages on behalf of your domain. Upon receiving an email, the recipient's server examines the SPF record associated with the sender's domain to confirm if the sending IP address is included. If the IP address is absent from the list, there is a possibility that the email could be classified as spam or outright rejected.

Here’s what a basic SPF record looks like:

v=spf1 include:_spf.google.com ~all

This document indicates that only the servers specified within Google's SPF range are authorized to dispatch emails on behalf of the domain.



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Why You Need an SPF Record Tester


Mistakes in your SPF record can greatly affect the success of email delivery. Utilizing an SPF record validation tool can assist in pinpointing:

  • Syntax errors

  • Redundant entries

  • Multiple SPF records

  • Exceeded DNS lookup limits

  • Invalid IPs or domains

Verifying your SPF record confirms that your setup adheres to RFC standards and operates correctly on all mail servers. Visit www.autospf.com for more details.

How to Use an SPF Record Tester

Most SPF testing tools work in a similar way:


Step 1: Locate Your Domain's SPF Record

Use a DNS lookup tool or command like:

nslookup -type=TXT yourdomain.com

This retrieves the current SPF record published in your domain’s DNS settings.


Step 2: Enter Your Domain into an SPF Tester Tool

Input your domain into a reliable SPF testing tool, such as:

  • MXToolbox SPF Checker

  • DMARC Analyzer SPF Tool

  • SPF Survey by Kitterman

  • Google Admin Toolbox

These instruments replicate an SPF verification process, examine the format of the record, and provide feedback on:

  • Record validity

  • DNS lookup count

  • Missing or incorrect IP addresses

  • Overlapping includes


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Step 3: Review the Results Carefully

Pay attention to:

  • Regardless of whether the record concludes with ~all, -all, or ?all.

  • The presence of multiple SPF records is not permitted and requires rectification.

  • Any inclusions that lead to over 10 DNS queries, surpassing the SPF threshold.

Fixing Multiple SPF Records: Best Practices


Having more than one SPF record on a domain is a fatal misconfiguration that results in SPF failure. Here’s how to fix it:

  • Combine All Entries into a Single SPF Record: If you are utilizing several email platforms, such as Google Workspace, Mailchimp, or Salesforce, consider consolidating them into a single record as illustrated below:

    v=spf1 include:_spf.google.com include:mailchimp.com include:_spf.salesforce.com ~all


  • Remove Redundant Entries: Eliminate any redundancies and streamline the record to maintain clarity while adhering to the DNS lookup limit.

  • Use Only One “v=spf1”: An effective SPF configuration should include a single SPF record for each domain. This record must start with v=spf1, include all relevant mechanisms and modifiers, and conclude with either ~all or -all.

  • Monitor the DNS Lookup Limit: The SPF protocol permits a maximum of 10 DNS lookups. Excessive use of include mechanisms can quickly surpass this threshold, resulting in failed SPF evaluations. To mitigate this issue, consider utilizing online SPF flattening tools to lower the number of lookups required, or, if feasible, consolidate your email services under a single provider.

  • Update Your DNS Settings Properly: After you have consolidated and refined the SPF record, access your DNS provider's interface to update the current TXT records with the revised SPF entry. Please note that updates generally take effect within a few minutes to several hours, depending on the Time to Live (TTL) settings configured for your DNS.