Privacy Policy — Earfish

Last updated: 2026-08-04

Earfish (“the Extension”, also 耳朵鱼) provides AI bilingual captions on YouTube. This policy describes what data we process and why.

1. What we process

• Video identifiers (YouTube video_id) for the page you open.
• Public caption text and timestamps harvested from YouTube’s official captions on the page, used only to produce translations.
• Translated captions returned to your browser for display.
• Install identifier (random id stored in extension storage) to enforce free quota and subscription status.
• Usage metering (seconds of video content associated with your install) for free tier and billing.

2. What we do not collect

• YouTube passwords, cookies, or pot tokens (these stay in the page and never leave your browser for that purpose).
• Your Google account content beyond the public watch page you open.
• Payment card numbers (handled by Stripe if you subscribe).

3. Why we process data

• To generate and display bilingual captions (core product function).
• To cache translations of public videos so the same video is not re-translated for every user (cost and speed).
• To enforce free 2-hour quota and paid subscription entitlements.

4. Sharing

Caption text is sent to our API and may be processed by our AI translation provider (e.g. DeepSeek) solely to produce translations. We do not sell your personal data. Payment is processed by Stripe.

5. Storage

Install quota records and shared translation caches are stored on our servers. Cached translations are derived from public captions and may be reused for other users of the same public video.

6. Your choices

• Uninstall the Extension to stop further collection from your browser.
• Contact us to request deletion of your install quota record (provide install id if available).

7. Contact

For privacy requests, contact the developer via the Chrome Web Store listing support email.