Privacy Policy

Effective: October 20, 2026 · Applies to: the LiveSubtitle browser extension and website

This page is currently available in Chinese and English only. Feature details are on the home page in your language.

Our design principle

If data can stay on your computer, it does.

LiveSubtitle is a local-first extension: subtitle cache, settings and API keys all live in your browser by default. Data leaves your device only when you actively use a feature that needs the network — cloud translation, cloud AI subtitles, AI summaries, signing in, or paying. So this policy is organised by where the data lives rather than by legal terminology.

1. Data stored on your device

This data is not uploaded to our servers:

• Settings: language preference, translation channel, interface options, per-site switches;
• Keys you enter: your own third-party API keys, model names and custom endpoint URLs;
• Subtitle cache and working data: fetched subtitles, transcripts, offline model records and backups;
• On-device transcription: with SenseVoice / Zipformer, audio is processed inside your browser — never written to disk, never uploaded.

This data stays on your device until you clear the cache, reset settings or uninstall the extension.

2. Account data

If you register an account or use Pro, we process:

• Email address, and whether it has been verified;
• Display name and avatar URL (provided by Google when you sign in with Google);
• Google user identifier (used only to recognise the same Google account; it contains no password);
• A one-way hash of your password plus a random salt (PBKDF2-HMAC-SHA256; irreversible — we cannot recover your password);
• Account status and registration time.

2.1 Sign-in sessions

• A hash of the refresh token (the token itself is never stored, only its hash, used to tell whether a session is valid);
• Browser user agent and IP address — for security auditing only (spotting unusual sign-ins, preventing account theft);
• Session creation and expiry times.

2.2 Usage records

• Which feature you used, how much of it (translation characters / audio seconds / summary characters), which model, and when;
• Purpose: billing and quota settlement, troubleshooting, and showing you your own usage report.

We do not record your browsing history, and we do not record which videos you watched.

3. What is sent when you use networked features

The following happens only when you actively use the corresponding feature, sends only what is needed to complete that one request, and is discarded once processed.

3.1 Cloud translation and AI summaries (Pro)

• Sent: the subtitle text you chose to translate or summarize, plus the video title;
• Not sent: the full video, audio files, your browsing history;
• Processed by: Cloudflare Workers AI (underlying models are Meta's Llama 3.1 and OpenAI's Whisper).

3.2 AI subtitles (Pro / free trial)

• Sent: small audio chunks split locally by the extension;
• Not sent: the full video file, or any visual content;
• Processed by: Cloudflare Workers AI (Whisper large-v3-turbo).

3.3 Payments

• Handled by Paddle.com Market Ltd. as merchant of record;
• We receive transaction and subscription identifiers (subscription ID, customer ID, subscription status, billing period, amount) to activate and manage Pro;
• We never see or store your card number, CVV or Alipay / WeChat Pay credentials.

3.4 Service email

• We use Resend to send essential service mail such as address verification, password resets and subscription status changes;
• Only your email address and the content of that message are passed along.

3.5 Google sign-in

• Only if you choose "Sign in with Google" do we verify your identity with Google and receive your user identifier, email, display name and avatar URL.

4. What we do not collect

• No tracking cookies, no advertising identifiers, no ad profiling;
• No Google Analytics, Baidu Analytics, PostHog or similar third-party analytics;
• No contacts, SMS, precise location or photo library data unrelated to the Service;
• No reading or uploading of browser data or other websites' content unrelated to what you're doing;
• We do not sell or rent your personal information, and we do not give data to data brokers.

5. How we use this data

• Providing features: sign-in, quota settlement, AI request processing;
• Keeping things secure: spotting unusual sign-ins, preventing account theft and quota abuse;
• Supporting transactions: handling subscriptions, refunds and receipts;
• Service communication: mail you trigger (verification, password reset) and necessary subscription notices;
• Improving the product: only aggregated statistics that contain no personal identifiers (for example overall usage of a feature).

We never use your subtitles, audio or account content for advertising.

6. How long we keep data

• Account information: kept until you delete your account. After deletion we remove or anonymise it within 30 days;
• Sessions: kept up to 30 days after expiry for security auditing, then cleaned up automatically;
• Usage records: kept for 12 months for reconciliation and dispute handling, after which only aggregate statistics remain;
• Content you submit to AI: not retained separately; it exists only briefly while a request is handled;
• Transaction records: retained by Paddle under its own compliance obligations (typically the period tax law requires);
• On-device data: stays on your device, outside our control, until you clear it.

7. Your choices and rights

At any time you can:

• View your account information and usage — on the extension's usage page;
• Correct inaccurate information (such as your display name);
• Export a copy of your data;
• Delete your account — email support@livesubtitle.app and we'll verify your identity and act;
• Withdraw consent — stop using the Service and delete your account;
• Turn off networked features — use only local features and your data never leaves your computer.

If you are in the EU, the EEA, the UK, Switzerland, California or another jurisdiction with similar legislation, the law may grant you additional rights (such as access, correction, erasure, restriction of processing, or the right to complain to a regulator). We respect those rights too, and we won't treat you differently for exercising them.

8. Security

• HTTPS everywhere;
• Passwords stored as PBKDF2 one-way hashes, so even a database leak cannot reveal the original password;
• Sign-in credentials use short-lived access tokens plus revocable refresh tokens, with only the hash stored;
• Least privilege: our servers access only the data needed to deliver the features.

Please understand, though, that no system can guarantee absolute security. If an incident could affect your data, we will notify you as the law requires.

9. Third-party services

To run the Service, necessary data is passed to the providers below, which may process it only within the scope of their own service:

• Cloudflare — server hosting, database and network acceleration;
• Cloudflare Workers AI — running AI translation, summaries and audio transcription (underlying models from Meta and OpenAI);
• Paddle — payment collection, billing and tax, refunds;
• Resend — sending service email;
• Google — authentication when you choose to sign in with a Google account.

Beyond that, we disclose information only where required by law or necessary to protect the safety of users and the public.

If you configure your own third-party service in the extension, data goes directly to that service according to your settings, under its own privacy policy, outside our control.

10. International transfers

Our servers and the providers above may be located outside your country or region. Using networked features means the relevant data will be transferred to and processed on servers outside your jurisdiction. We require providers to protect that data to a standard no lower than this policy.

11. Children

The Service is not intended for children under 13. If you are below the age of majority where you live, please use it with a guardian's consent.

12. Policy changes

If this policy changes we update the date at the top of this page. Substantive changes to what we collect or how we use it will be communicated by email or an in-product notice.

13. Contact

For any privacy question or data request: support@livesubtitle.app. We usually reply within 1–2 business days.

If you believe we've handled your data improperly, you may also complain to a data protection authority in your country or region. We'd appreciate the chance to hear from you first and resolve it directly.