Privacy Policy

Last updated: April 2026

What data we collect

• Resource sizes: The extension uses the browser Performance API to collect transfer sizes (in bytes) of resources loaded by web pages you visit. This is used to estimate carbon emissions.
• Hostnames (opt-in only): If you enable "Check green hosting status" in settings, the hostname (e.g., "example.com") of each page is sent to the Green Web Foundation API to check renewable energy hosting. This feature is disabled by default. Only the hostname is sent — no full URLs, paths, or query parameters. Responses are cached locally for 24 hours.

What we do NOT collect

• We do not read, store, or transmit your personal browsing content, form data, cookies, or credentials.
• We do not use any tracking, analytics, or telemetry services.
• We do not collect or transmit any personally identifiable information.

Where data is stored

All data — including carbon history, settings, and cached hosting lookups — is stored locally on your device using chrome.storage.local and chrome.storage.session. No data is sent to any server controlled by Carbonlite.

Incognito mode

In incognito windows, Carbonlite does not save any history data, does not make external API calls, and discards all tab data when the window closes.

Data retention

History entries are automatically deleted after 30 days. Per-domain history is capped at 100 entries. You can clear all data at any time from Settings. Uninstalling the extension removes all stored data.

Third-party services

The only external service contacted (when opted in) is the Green Web Foundation API (api.thegreenwebfoundation.org) for green hosting checks. Their privacy policy is available at thegreenwebfoundation.org/privacy-policy.

Permissions

• sidePanel: Display the carbon analysis UI in a persistent side panel.
• storage: Persist settings, carbon history, and cached hosting data locally on your device.
• webNavigation: Detect page loads to trigger automatic carbon analysis.
• tabs: Identify Chrome internal pages (which cannot be analyzed) and respect Incognito privacy.
• Content script (all websites): Collect resource transfer sizes via the browser Performance API to calculate carbon emissions. No page content is read.
• host_permissions (thegreenwebfoundation.org): Check green hosting status (opt-in only, disabled by default).

Contact

Questions or concerns? Open an issue at github.com/rapidminds-tech/carbonlite/issues.