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Preview of DomainIntel - WHOIS, DNS, SSL & Security

DomainIntel - WHOIS, DNS, SSL & Security by Full Cycle Development Group

One click: the security grade, SSL certificate, DNS and email authentication for the site you are on.

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About this extension
See who a site really is, in one click.

DomainIntel checks the site in your active tab and shows what public records say about it: an overall security grade, whether the TLS certificate is trusted and when it expires, which DNS records exist, and whether the domain publishes SPF and DMARC for email authentication.

What you get, without leaving the page
  • A security grade from A+ to F, with the score behind it
  • TLS certificate status: trusted, expired, or not trusted at all, plus days remaining and the issuing authority
  • DNS at a glance: A records, MX records, and how many nameservers answer for the domain
  • Email authentication: whether SPF and DMARC are published
  • The domain's registrar and expiry date
  • A link through to the full report, including WHOIS, subdomains and HTTP security headers

It tells a broken certificate from a missing one

Plenty of tools show a padlock if any certificate is present. This one separates three situations that mean very different things: no HTTPS at all, a certificate a browser would reject (expired, self-signed, or issued for a different hostname), and a genuinely trusted certificate. They are graded differently because they are different problems.

Built to stay out of your way

Nothing runs until you click the toolbar button. There is no background process watching your browsing and no script injected into the pages you visit. When you do click, the only thing sent is the hostname of your current tab. Not the URL, not the path, not the page content, and nothing about you.

Free, no account, no sign-up.

Full reports and more tools at https://domainintel.app
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Permissions and data

Optional permissions:

  • Access your data for domainintel.app

Required data collection, according to the developer:

  • Browsing activity
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Version
1.0.3
Size
25.67 KB
Last updated
10 days ago (Sep 21, 2026)
Related Categories
  • Web Development
  • Privacy & Security
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