Privacy Policy

CSS Checker Chrome Extension

Last Updated: March 31, 2026

Overview

CSS Checker is committed to protecting your privacy. This Privacy Policy explains how our Chrome extension accesses, uses, and protects your data.

What Data We Access

Our extension requires access to page data to provide CSS inspection functionality. Specifically, we access:

  • DOM & CSS Data: We read the DOM structure, computed CSS properties, and stylesheet contents of the active tab to display style information
  • Page Metadata: We access the page URL and title for display in the extension interface
  • User Preferences: We store your theme selection and active tab preference locally

What We DO NOT Access:

  • Form data or user inputs on web pages
  • Passwords, cookies, or authentication tokens
  • Personal correspondence beyond inspected pages
  • Your contacts or address book
  • Other Google services (Calendar, Drive, etc.)

How We Use Your Data

We use the accessed data solely for the following purposes:

  • CSS Inspection: Read and display computed styles, box model, and selector information for elements you inspect
  • CSS Validation: Send public stylesheet URLs to the W3C CSS Validator API for validation
  • XPath Building: Evaluate XPath expressions against the page DOM to highlight matching elements
  • Display Information: Show you CSS properties, colors, fonts, and assets in the extension interface

Data Storage

What We Store:

  • User preferences (theme, active tab) in Chrome's local extension storage
  • No other data is stored, cached, or persisted

What We DO NOT Store:

  • Page content, DOM data, or CSS properties
  • URLs or browsing data
  • Personal correspondence
  • Any sensitive personal information beyond what's necessary for local preferences

Where Data is Stored:

  • All data stays in Chrome's local extension storage on your device
  • No data is sent to any server owned or operated by us
  • The only external request is W3C CSS validation, which sends public stylesheet URLs to jigsaw.w3.org

Permissions and Access

Our extension requests the following Chrome permissions:

  • activeTab: Allows reading DOM and CSS properties of the page you're viewing. This is the minimum permission required for our functionality.
  • sidePanel: Allows displaying the CSS Checker interface in Chrome's side panel

Every action that uses these permissions requires your explicit consent - we never automatically read or modify page content.

Data Sharing and Third Parties

We DO NOT:

  • Sell your data to third parties
  • Share your data with advertisers
  • Use your data for marketing purposes
  • Transfer your data to data brokers or resellers
  • Use your data for AI training or machine learning

Limited Data Sharing:

We only share your data in the following circumstances:

  • With your explicit consent
  • To comply with legal obligations
  • For security purposes (investigating abuse or bugs)

Data Security

We implement industry-standard security measures to protect your data:

  • All data processing happens locally in your browser
  • Extension permissions follow the principle of least privilege
  • No personal data is transmitted over the network
  • Regular security audits and updates

Your Rights and Control

You have complete control over your data:

  • Revoke Access: You can revoke our extension's access at any time via Chrome Extension Settings
  • Uninstall: Uninstalling the extension immediately stops all data access
  • Data Deletion: Contact us to request deletion of your stored data
  • Data Access: Request a copy of your stored data by contacting us

GDPR Compliance

For users in the European Union, we comply with GDPR requirements:

  • Data Minimization: We only collect the minimum data necessary
  • Purpose Limitation: Data is only used for stated purposes
  • Transparency: Clear explanation of data usage (this policy)
  • User Rights: Right to access, rectification, erasure, and data portability

Children's Privacy

Our extension is not intended for children under 13 years of age. We do not knowingly collect data from children.

Changes to This Policy

We may update this Privacy Policy from time to time. We will notify users of significant changes by:

  • Updating the "Last Updated" date at the top of this policy
  • Displaying a notice in the extension interface

Contact Us

If you have questions about this Privacy Policy or our data practices, please contact us: