Heimdall SEO – Privacy Policy

Last updated: October 24, 2026

Heimdall SEO is a Chrome extension published by TL;DR SEO (tldr-seo.fr). It audits the on-page SEO of the web page you are viewing. This policy explains what the extension does — and does not do — with your data.

In short

  • Heimdall SEO does not collect, store, sell or share any personal data.
  • All analysis runs locally in your browser. Nothing is sent to TL;DR SEO or to any third-party server.
  • There are no accounts, no analytics, no tracking and no advertising.

What the extension reads

When you open the Heimdall SEO side panel on a tab, the extension reads the content of that page (title, meta tags, headings, images, links, text, hreflang tags, structured data, Open Graph and Twitter tags) and the HTTP status and redirects of that page. This information is only used to display the audit in the side panel. It is kept in memory while the panel is open and is discarded when you close it or the tab.

What the extension saves

The only thing Heimdall SEO saves is your choice of light or dark theme for the side panel. It is stored locally in your browser, is never sent anywhere, and is deleted when you remove the extension.

Network requests

To check for broken links and hreflang targets, the extension sends lightweight HEAD requests directly from your browser to the URLs found on the audited page. These requests are sent without cookies or credentials, exactly like an anonymous visitor. Their results are only displayed to you.

Some buttons open external tools in a new tab (for example the Schema.org validator or Google’s Rich Results Test) with the current page URL. This only happens when you click them.

The fonts used by the extension are bundled with it: no request is made to Google Fonts or any other font service.

Permissions

  • activeTab, scripting: analyse the page you are viewing and highlight elements on it.
  • sidePanel: display the audit in Chrome’s side panel.
  • webRequest, webNavigation: read the HTTP status code and redirect chain of the audited page.
  • Access to all websites: audit any site you choose and check the status of the links it contains.

Chrome Web Store user data policy

The use of information received from Chrome APIs complies with the Chrome Web Store User Data Policy, including the Limited Use requirements.

Changes and contact

If this policy changes, the updated version will be published on this page with a new date. For any question, see the contact details in our legal notice.