Security
What happens to your video and data
The short version: the video is processed in your browser, only the audio is sent for transcription, and payments are handled by Paddle. Here is the detailed data flow.
Last updated: 31 October 2026
Data flow
| Data | Where it goes | Why |
|---|---|---|
| Video file | Stays in your browser | Audio extraction and preview happen locally. We do not store a video caption project. |
| Extracted audio | Transcription provider (Groq; xAI for multi-speaker) | Returns timed words and captions. Provider retention and training terms apply. |
| Account and billing data | Our Postgres database + Paddle | Sign-in, subscription status, orders, invoices and support. |
| Custom fonts (paid plans) | Cloudflare R2 | So the editor can load the font you uploaded. |
| Payment card data | Paddle (Merchant of Record) | Paddle processes payment, tax and receipts. We do not store card numbers. |
Account security
- Sign-in uses Google OAuth. We do not store passwords.
- Sessions are HTTP-only cookies and can be ended by logging out.
- You can export your account data or delete your account from Account → Privacy and data.
- Deleting your account cancels an active subscription and anonymizes profile fields; order records are retained for tax and accounting.
Infrastructure
The site runs on Cloudflare Workers with Cloudflare Hyperdrive for Postgres. Media and custom fonts use Cloudflare R2. Payment processing and tax are handled by Paddle. Access to production systems is limited to the people who operate the service.
Reporting a vulnerability
Email support@autocaptions.org with the subject “Security report”. Include the affected URL, reproduction steps, and the impact you believe it has. Do not access other users’ data, run destructive tests, or disclose the issue publicly before we have had a reasonable chance to respond. We will acknowledge receipt and keep you updated.
Related
- Privacy Policy — what we collect and why.
- Cookie Policy — cookies and local storage.
- Terms of Service — acceptable use and liability.