PRIVACY POLICY

INTRODUCTION

CARBN.ZONE (“we”, “our”, “us”) is operated by Danil Koltsov. This Privacy Policy explains how we collect, use, and protect your information when you use CARBN.ZONE (carbn.zone).

By using CARBN.ZONE you agree to this Privacy Policy.

INFORMATION WE COLLECT

Strava Account Data

When you connect your Strava account via OAuth 2.0, we receive:

• —Your Strava profile (name, profile photo, athlete ID)
• —Your cycling activities and associated metrics (power, heart rate, cadence, distance, elevation, GPS routes)
• —Activity timestamps and duration

Data You Provide

• —FTP (Functional Threshold Power) — stored locally in your browser
• —HR Max — stored locally in your browser
• —Training preferences and settings

Automatically Collected

• —Browser type and version
• —Access timestamps for security purposes

HOW WE USE YOUR DATA

We use your data solely to:

• —Display your training analytics and performance metrics
• —Calculate training zones, TSS, and power estimates
• —Generate training insights on your request

• —We do NOT use your data to train AI or machine learning models.
• —We do NOT sell your data to third parties.
• —We do NOT share your data with other users.

DATA STORAGE

• —Strava access tokens are stored securely server-side in your session
• —Performance settings (FTP, HR zones) are stored in your browser's localStorage and never transmitted to our servers
• —Cached activity data is stored in your browser's localStorage only
• —We do not maintain a persistent database of your Strava activities

STRAVA DATA

Your activity data is fetched directly from Strava's API on your request and cached temporarily in your browser. We comply fully with Strava's API Agreement and Brand Guidelines.

You can revoke CARBN.ZONE's access to your Strava data at any time via Strava Settings → My Apps.

DATA RETENTION

Since we do not store your data server-side, there is no data to delete from our systems. Clearing your browser's localStorage removes all locally cached data. Revoking Strava access removes all authentication tokens.

COOKIES

We use only essential session cookies required for authentication. We do not use tracking, advertising, or analytics cookies.

THIRD-PARTY SERVICES

• —Strava — activity data provider (strava.com/legal/privacy)
• —Vercel — hosting provider (vercel.com/legal/privacy-policy)
• —Anthropic Claude API — used to generate training insights on your explicit request only

YOUR RIGHTS (GDPR)

If you are in the EU/EEA, you have the right to:

• —Access your personal data
• —Request deletion of your data
• —Object to processing
• —Data portability

Contact: privacy@carbn.zone

CHILDREN'S PRIVACY

CARBN.ZONE is not intended for users under 16 years of age.

CHANGES TO THIS POLICY

We may update this policy. Changes will be posted on this page with an updated date. Continued use constitutes acceptance.

CONTACT

Questions about this Privacy Policy:

• —Email: privacy@carbn.zone
• —Website: carbn.zone