Privacy Policy

Effective date: 1 March 2026 · Last updated: 3 March 2026

CarbonFirefly ("we", "us", "our") provides a browser extension and web calculator that estimate the carbon footprint of AI conversations so that you can manage and reduce this. We are committed to protecting your privacy. This policy explains what data the CarbonFirefly browser extension and website collect, how it is used, and how you can control it.

    The key principle: CarbonFirefly never stores or transmits
    your prompts, messages, or AI response content.
  

1. What We Collect

1.1 Carbon Metrics (Collected Automatically)

When you use an AI platform with the extension active, we collect metadata about the query:

AI model name and provider (e.g., "GPT-4o", "OpenAI")
Estimated input and output token counts
Calculated carbon estimate (gCO₂e)
Response latency (time to first token, tokens per second)
Query timestamp
Modality type (text, image, audio, video)

    This data is stored locally in your browser (IndexedDB). When you
    create an account and connect the browser extension, dashboard sync is
    enabled by default so that we can provide you with information
    that helps you reduce the carbon footprint of your AI use, and so that we can
    improve the way we calculate carbon usage. You can disable sync at any time via
    the extension settings (see Section 3).
  

1.2 User Settings

Your preferences are stored in chrome.storage.sync:

Selected data centre region
Overlay display position and unit preference
Telemetry opt-in/out preference

These sync across your Chrome browser instances via your Google account. No other party has access.

1.3 What We Never Collect

Your prompts, questions, or messages to AI platforms
AI-generated response text or content
Personal emails, files, or browsing history
Passwords or financial information
Location data (other than data centre region) or IP addresses (the extension does not make network requests unless you opt in)

2. Anonymous Telemetry (Opt-In)

CarbonFirefly includes optional, anonymous usage telemetry powered by PostHog. This is disabled by default and requires your explicit opt-in via Settings → Privacy. No telemetry data is ever sent unless you enable it.

When enabled, we collect:

Aggregated model distribution (e.g., "40% GPT-4o, 30% Claude Sonnet")
Average query sizes and region breakdown
Extension version and browser type

We never collect via telemetry:

Prompt or response content
Personally identifiable information (PII)
Individual query details

Telemetry data is aggregated locally and transmitted at most once every 24 hours. Differential privacy noise is applied to all counts before transmission. You can disable telemetry at any time and preview exactly what would be sent.

3. Dashboard Sync (Enabled by Default)

When you create a CarbonFirefly account and connect the browser extension, dashboard sync is enabled by default. Your carbon totals are synced to your online dashboard at carbonfirefly.ai. This allows us to provide you with information that helps you reduce your AI carbon footprint, and it helps us improve the way we calculate carbon usage. You can disable sync at any time in the extension settings.

What is synced:

Carbon metrics (model, token counts, carbon estimate, timestamp)
Session summaries and daily totals

What is never synced:

Prompt or response text
Browsing activity outside supported AI platforms

Synced data is transmitted over HTTPS to api.carbonfirefly.ai and stored in our encrypted database. You can delete your synced data at any time via the dashboard, or by deleting your account.

4. Email Communications (Enabled by Default)

When you create a CarbonFirefly account, email communications are enabled by default. We may send you:

Personal carbon footprint recommendations based on your usage
Progress reports showing how your AI carbon footprint has changed
Tips for reducing the environmental impact of your AI use

We will never spam you, sell your email address, or share it with any third party. You can disable email communications at any time via the extension settings. We use your email address solely for account management and the communications described above.

5. Data Storage and Retention

Data	Location	Retention
Query history (prompts and responses are never stored)	Local browser (IndexedDB)	90-day rolling window
User settings	chrome.storage.sync	Until you change or uninstall
Telemetry buffer	Local browser	Flushed every 24 hours (if enabled)
Dashboard data	CarbonFirefly servers (encrypted)	Until you delete it or your account

6. Third-Party Services

Service	Purpose	Data Shared
PostHog	Anonymous usage analytics	Aggregated model/region stats (opt-in only)
Google OAuth	Account authentication	Email address (for sign-in only)

We do not sell, rent, or share your data with any other third parties.

Google API Limited Use Disclosure: The use of information received from Google APIs will adhere to the Chrome Web Store User Data Policy, including the Limited Use requirements.

7. Your Controls

You have full control over your data:

Export: Download all your local data as CSV or JSON via Settings
Delete: Clear all local data via Settings → Data → Clear all data
Telemetry: Disable anonymous telemetry at any time via Settings → Privacy
Preview: See exactly what telemetry data would be sent before it is
Sync: Disable dashboard sync via Settings → CarbonFirefly Preferences; delete your account to remove server data
Email: Disable email communications at any time via Settings → CarbonFirefly Preferences
Uninstall: Removing the extension deletes all local data

8. Permissions

The extension requests the following Chrome permissions, each for a specific purpose:

Permission	Why It's Needed
`activeTab`	Display the carbon overlay badge on AI platform pages
`storage`	Save your settings (region, display preferences) across sessions
`downloads`	Export your query history as CSV or JSON when you request it
`alarms`	Schedule periodic sync of carbon data to your dashboard
`scripting`	Inject content scripts to detect AI model usage on supported platforms

Content scripts run only on ChatGPT (chatgpt.com), Claude (claude.ai), and Gemini (gemini.google.com). The extension does not access any other websites.

9. Children's Privacy

CarbonFirefly is not directed at children under 13. We do not knowingly collect personal information from children.

10. Changes to This Policy

We may update this privacy policy from time to time. Changes will be posted on this page with an updated effective date. For significant changes, we will notify users through the extension's update notes.

11. Contact

If you have questions about this privacy policy or your data, please contact us at:

Email: privacy@carbonfirefly.ai
Website: www.carbonfirefly.ai

CarbonFirefly Ltd

Company number: 16987128

Registered address: 11 Wykeham Terrace, Brighton, BN1 3FF, United Kingdom