DNS Doctor

Example reports

How well-known domains answer the question every receiving mail server asks: was this message really sent by you, and what should happen if it wasn't? Each row links to the full report — the same free scan you can run on any domain. Grades reflect the most recent scan and update as domains change their records.

Email service providers

The platforms most “is my mail set up right” questions are about — each sender's own domain is the reference config its customers measure against.

  • mailchimp.comGrade BenforcingThe marketing ESP whose setup guide millions have followed.
  • sendgrid.comGrade BenforcingTransactional giant; domain authentication is its customers' daily support question.
  • postmarkapp.comGrade BenforcingTransactional specialist known for deliverability rigor — read its own records closely.
  • klaviyo.comGrade BenforcingE-commerce marketing sender; dedicated sending domains are its onboarding staple.
  • brevo.comGrade AenforcingThe Sendinblue rebrand, with a huge EU small-business base debugging DNS.
  • constantcontact.comGrade BenforcingLegacy SMB mailing giant with a long tail of setup questions.
  • activecampaign.comGrade BenforcingMarketing automation whose authentication guides are pasted everywhere.
  • mailgun.comGrade BenforcingDeveloper email API; domain verification is step one of every integration.
  • amazonses.comGrade AenforcingAWS's raw sending pipe — the domain every SES tutorial builds on.
  • customer.ioGrade BenforcingBehavioral messaging platform; sending-domain setup gates its onboarding.
  • kit.comGrade BenforcingCreator newsletter platform, the successor name to ConvertKit.
  • convertkit.comGrade Bmonitor-onlyThe original ConvertKit domain — rebrand-era configs reward comparison.
  • beehiiv.comGrade BenforcingFast-growing newsletter platform sending at serious scale.
  • substack.comGrade BenforcingThe newsletter platform whose headers land in millions of inboxes daily.
  • mailerlite.comGrade AenforcingSMB newsletter tool with a large self-serve DNS-setup audience.
  • resend.comGrade BenforcingThe developer-favorite email API; its own domain is its best documentation.

Mailbox providers

The companies that wrote the sender requirements — and their own domains' answers to them.

  • google.comGrade BenforcingThe company that made DMARC a condition of bulk delivery in 2024.
  • gmail.comGrade Bmonitor-onlyThe consumer domain of the requirements era's chief enforcer.
  • outlook.comGrade Bmonitor-onlyMicrosoft's consumer mail domain, behind the 2025 requirements wave.
  • microsoft.comGrade BenforcingRoutinely the most-imitated brand in phishing rankings.
  • yahoo.comGrade BenforcingCo-author of the February 2024 bulk-sender requirements.
  • icloud.comGrade BenforcingApple's mail domain; its postmaster rules quietly demand authentication too.
  • zoho.comGrade AenforcingThe SMB workspace suite with an enormous setup-guide audience.
  • protonmail.comGrade BenforcingThe privacy-first provider — how encryption specialists publish policy.

SaaS platforms

Products that send mail while their customers do business — the configs behind everyday notification mail.

  • salesforce.comGrade BenforcingCRM mail at enormous scale; customers' sending-domain setup questions never stop.
  • hubspot.comGrade BenforcingMarketing suite whose connected sending domains customers debug daily.
  • zendesk.comGrade BenforcingSupport-desk mail, sent on behalf of thousands of customer brands.
  • intercom.comGrade BenforcingCustomer-messaging mail with a sending domain per workspace.
  • shopify.comGrade BenforcingStore notification mail for a meaningful share of e-commerce.
  • atlassian.comGrade BenforcingJira and Confluence notifications flood corporate inboxes.
  • slack.comGrade AenforcingWorkspace notification mail — compare with its owner Salesforce's config.
  • github.comGrade BenforcingNotification mail every developer receives; the subdomain story rewards reading.
  • docusign.comGrade AenforcingSignature-request phishing is a staple — which makes its real config instructive.
  • stripe.comGrade BenforcingPayment mail that phishers love to imitate.
  • zoom.usGrade BenforcingMeeting-invite phishing has impersonated it since 2020.

Heavily-imitated brands

The names phishers wear most; what each domain's DNS tells receivers to do about it.

  • paypal.comGrade BenforcingWhere DMARC began — the PayPal–Yahoo anti-phishing pilot became the standard itself.
  • amazon.comGrade AenforcingRoutinely among phishing's most-imitated brands.
  • apple.comGrade BenforcingA constant target of receipt-and-invoice phishing.
  • netflix.comGrade BenforcingThe classic “your account is on hold” phish target.
  • facebook.comGrade BenforcingAn early DMARC adopter at extreme scale.
  • linkedin.comGrade BenforcingConnection-request phishing hardened this config early.
  • chase.comGrade AenforcingUS banking's most-spoofed name, in a famously strict-enforcing sector.
  • fedex.comGrade AenforcingOne of delivery-notification phishing's longest-running targets.
  • dhl.comGrade BenforcingRoutinely top-three in global brand-phishing rankings.
  • usps.comGrade AenforcingPackage-tracking phishing at national scale.

Government

The mandated sector — US federal domains have been under an enforcement directive since 2018, the UK since 2016.

  • cisa.govGrade AenforcingThe agency behind the federal DMARC mandate, BOD 18-01.
  • dhs.govGrade BenforcingThe department that issued the 2017 directive — enforcement due within a year.
  • whitehouse.govGrade BenforcingThe most-watched .gov configuration there is.
  • irs.govGrade BenforcingTax-season phishing's biggest target, under federal mandate.
  • nasa.govGrade BenforcingA sprawling federal mail estate under the same directive.
  • gov.ukGrade BenforcingThe UK required DMARC for government services back in 2016.

Universities

Adoption studies consistently rank higher education last on enforcement — four famous names to compare.

  • mit.eduGrade Bmonitor-onlyThe sector's most famous name — a natural first comparison.
  • harvard.eduGrade BenforcingOne of the most-watched names in academic email.
  • stanford.eduGrade BenforcingA large research-university mail estate — scale is the sector's whole challenge.
  • berkeley.eduGrade BenforcingA university mail estate worth reading against its sector's reputation.

Registrars & DNS hosts

Where everyone else edits their DNS — and the records these companies publish for themselves.

  • godaddy.comGrade BenforcingThe registrar where much of the world edits its DNS.
  • namecheap.comGrade AenforcingRegistrar to millions of side projects and their TXT records.
  • cloudflare.comGrade BenforcingThe DNS provider itself — the config behind the dashboard.
  • squarespace.comGrade BenforcingThe website builder where many owners meet DNS for the first time.
  • wordpress.comGrade BenforcingHosts a meaningful share of the web; its mail config matters at scale.

Your domain

Every report above started as one pasted domain. See how yours compares — SPF, DMARC, DKIM, MX, DNS, blacklists and expiry, in one scan.