--- title: "What is Kitterman SPF, and How Does it Work? | DuoCircle" image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/resources/what-is-kitterman-spf-and-how-does-it-work/" --- DuoCircle # What is Kitterman SPF, and How Does it Work? Kitterman SPF is an SPF diagnostic tool published by Scott Kitterman in 2005, built on the RFC 7208-compliant pySPF (Python SPF) library. It checks whether a queried domain has an existing SPF record, verifies the record's syntax, compares the TXT and SPF record types, and runs a live SPF check of a message sent from a listed IP address. [ Talk to an Expert → ](/contact/) [ See what we make ](/products/) ## What is Kitterman SPF, and How Does it Work? ## What is Kitterman SPF, and How Does it Work? [Fix Your SPF Errors Now](/content/spf-permerror) ###### [EMAIL SECURITY SERVICES](/) ###### [PLANS AND PRICING](/email/outbound-smtp#pricingarea) ###### [SPF RECORDS](/email/spf-record-check) ### Preface Kitterman SPF is an SPF diagnostic tool by Kitterman Technical Service, Inc. that helps you check if there’s an existing [SPF record](/content/spf-records/spf-record-example) for the queried domain and does it has a **proper record syntax configuration**. ### What is Kitterman SPF? The Kitterman SPF tool was published by Scott Kitterman in 2005 in alignment with the RFC 7208 compliant [pySPF (Python SPF) library](/content/spf-record-tester/kitterman-spf) that checks if there’s a pre-existing SPF record for the queried domain. It also examines if the [TXT and SPF record](/resources/how-to-create-an-spf-txt-record) types for a domain are the same, calls the pySPF SPF record retrieval, and presents results as per the email’s source of origin. ![email security](https://media.mailhop.org/duocircle/images/2019/02/email-phishing-protection.png) ### How Does Kitterman SPF Check If You Already Have an SPF Record? Kitterman SPF checks TXT and SPF record types for the queried domain name and evaluates if the record found is valid or not. It performs a query for the [DNS record](https://en.wikipedia.org/wiki/List%5Fof%5FDNS%5Frecord%5Ftypes) of both TXT and SPF record types and presents the results. This is followed by the pySPF SPF record retrieval function (dns\_spf) to understand if both TXT and SPF records are the same. You receive a Kittermans SPF lookup report based on the examination. Next, SPF Kitterman performs a live [SPF check](/content/spf-record-checker) of a message of the queried domain sent from one of the IP addresses enlisted in the corresponding record. When the record ends in ‘all,’ Kitterman SPF knows what will be the result if no match is successful. However, you will see the ‘SPF record passed validation test with pySPF (Python SPF library)’ message when there’s an agreement between the **actual and expected results**. Domain administrators have to determine if the results are expected when there’s a redirect. You may also get an error message if there’s a syntax issue, and in the case of a complicated SPF record, Kitterman SPF test results may vary significantly. ![email security](https://media.mailhop.org/duocircle/images/2021/09/azure-tenant-migration.png) ## Ready to talk? Same-day response from someone technical. We tell you yes or no quickly. If yes, we get to work. [Talk to an Expert→](/contact/)[See what we make](/products/) ```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. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","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"}],"sameAs":["https://www.linkedin.com/company/duocircle","https://x.com/duocirclellc","https://www.facebook.com/duocirclellc","https://www.g2.com/products/phish-protection-by-duocircle/reviews","https://github.com/duocircle","https://www.crunchbase.com/organization/duocircle-llc"],"contactPoint":{"@type":"ContactPoint","contactType":"customer support","url":"https://support.duocircle.com"},"knowsAbout":["Email Security","Email Authentication","SPF","DKIM","DMARC","Phishing Protection","Spam Filtering","SMTP Relay","Email Deliverability","Email Forwarding"]} ``` ```json {"@context":"https://schema.org","@type":"WebSite","name":"DuoCircle LLC","url":"https://www.duocircle.com","description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","publisher":{"@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. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","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":"WebPage","name":"What is Kitterman SPF, and How Does it Work?","description":"Kitterman SPF is an SPF diagnostic tool published by Scott Kitterman in 2005, built on the RFC 7208-compliant pySPF (Python SPF) library. It checks whether a queried domain has an existing SPF record, verifies the record's syntax, compares the TXT and SPF record types, and runs a live SPF check of a message sent from a listed IP address.","url":"https://www.duocircle.com/resources/what-is-kitterman-spf-and-how-does-it-work/","speakable":{"@type":"SpeakableSpecification","cssSelector":[".page-answer",".duo-rich-text p:first-of-type"]},"dateModified":"2023-04-25T17:56:58.000Z","datePublished":"2023-04-25T17:56:48.000Z"},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"DuoCircle","item":"https://www.duocircle.com/"},{"@type":"ListItem","position":2,"name":"What is Kitterman SPF, and How Does it Work?","item":"https://www.duocircle.com/resources/what-is-kitterman-spf-and-how-does-it-work/"}]}] ```