Terms of Service

Effective: October 20, 2026 · Last updated: October 20, 2026

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

1. What these terms are

These are the terms between you and us covering your use of the LiveSubtitle browser extension and its related online services (together, the "Service"). Installing, registering for or using the Service means you have read and accepted these terms. If you don't accept them, please don't use the Service.

"We" and "us" mean LiveSubtitle, the operator of the Service. "You" means the individual using it.

2. What the Service is

LiveSubtitle is a browser extension. While you watch online video, it presents the video's subtitles as a scrollable, searchable text panel, and adds these capabilities:

• Subtitle panel: line-by-line display with click-to-seek, highlighting of the current line, pinyin search and folding by chapter;
• Translation: translate subtitles into other languages, using your browser's own translation or a third-party service or model you choose;
• AI subtitles: for videos with no subtitle track, extract the audio and produce a timestamped transcript;
• AI summaries: turn a whole transcript into sectioned key points;
• Export: save as txt / srt / vtt / ass / lrc / json.

The Service currently supports Bilibili (bilibili.com) and YouTube. We have no affiliation, agency or partnership relationship with Bilibili, YouTube or their operators; all trademarks belong to their respective owners. The Service does not provide or store video content itself.

The AI features require an internet connection and are carried out by our servers calling third-party AI models, subject to quotas. See the pricing page.

3. Accounts

• You can register with an email address or sign in with a Google account.
• You are responsible for everything that happens under your account, and you must provide accurate registration information.
• Accounts are for individual use only. Sharing, selling or bulk-activating accounts for others may lead to restrictions.
• Keep your credentials safe. If you believe your account has been compromised, contact us immediately.
• You can ask us to delete your account at any time; afterwards we handle your data as described in the Privacy Policy.

4. Free and Pro

• The free plan works indefinitely at no cost and is not a trial. The panel, search, chapter folding, export, floating subtitles, live subtitles and on-device transcription are all unmetered.
• Pro is a subscription that unlocks the AI line-by-line translation, AI subtitles and AI summaries that run on our servers.
• New accounts receive one-off trial credits: 5 AI subtitle jobs and 5 AI summaries. They do not expire and are not replenished monthly.

5. Payment, taxes and subscriptions

• Online payments are handled by Paddle.com Market Ltd. ("Paddle") as merchant of record. This means Paddle is the seller in the purchase transaction, is your counterparty, and issues receipts or invoices and calculates and remits applicable taxes.
• We receive only the subscription identifier, status, billing period and amount, used to activate and manage Pro. We never see or store your full card details.
• Pro renews automatically unless you cancel before the next billing period begins. The price is the one shown on the pricing page at the time of purchase.
• You can cancel at any time. After cancelling, Pro stays usable until the end of the period you paid for, and no further charges are made.
• We may change prices. Changes are announced in advance and apply only from your next billing period onwards.
• Before online payment goes live, you may receive Pro through a redemption code. Codes are for individual use, non-transferable and cannot be exchanged for cash.

6. Quotas and fair use

The AI features use a "one-off free trials + unlimited on Pro" structure:

• Free plan: 5 AI subtitle jobs and 5 AI summaries on registration. They are used up and not replenished monthly. AI line-by-line translation is not included; you can use your browser's own translation.
• Pro: AI subtitles, AI summaries and AI line-by-line translation are unmetered while the subscription is active. You should never need to count.
• One "job" means one video. A single video's audio is capped at 2 hours; one AI summary processes at most 100,000 characters of subtitle text.

6.1 Fair-use ceiling

"Unlimited" is meant for normal individual use. To stop automated scripts, resellers and similar abuse from exhausting resources, Pro carries the following ceilings. They sit far above any normal individual usage:

• AI subtitles: no more than 40 hours of audio per calendar month;
• AI line-by-line translation: no more than 5 million characters per calendar month;
• AI summaries: no more than 5 million tokens per calendar month.

Once a ceiling is reached, the feature pauses for the rest of that calendar month and resumes automatically the following month. If you believe your usage is normal and you were limited anyway, write to us — a human will review it.

6.2 How usage is measured

All usage is measured server-side by us (translation by characters, subtitles by audio duration). Numbers reported by the client are not relied upon. You can see your current usage on the extension's usage page.

7. Refunds and cancellation

Refund rules are set out separately in the Refund Policy, which forms part of these terms. In short: within 14 days of your first purchase, with the AI features essentially unused, you can request a full refund.

8. Acceptable use

You must not use the Service to:

• violate any applicable law or regulation;
• infringe anyone's copyright, privacy or other rights — for example, republishing generated subtitles commercially without authorisation;
• crack, decompile, bypass payment or quota limits, or disrupt the Service or other people's use of it;
• upload or process unlawful content;
• bulk-register accounts, share accounts, resell the Service or run it on others' behalf.

If you do, we may suspend or terminate your account. Where a paid period is involved, we refund the unused portion.

9. AI-generated content

AI translation, AI subtitles and AI summaries are produced by machine models and may be inaccurate, incomplete or biased. We make no accuracy guarantee. Do not use the output for legal, medical or financial purposes that require professional judgement. AI output is for your own reference and comprehension only.

AI-generated content does not represent our views. You are responsible for how you use it.

10. Content you submit and third-party services

• Ownership of the subtitle text and audio chunks you submit for AI processing stays with you or the original rights holder. We process them only within the scope of your request, for no other purpose.
• If you configure your own third-party service or API key in the extension, your relationship with that service is governed by its own terms. We neither control it nor accept responsibility for it.
• When you use Pro's cloud AI, the necessary content is sent to the model services we use, discarded after processing, and never used to train models. See the Privacy Policy.

11. Intellectual property

The software, interface, trademarks and documentation of the Service belong to us or the relevant rights holders. What you receive is a personal, non-transferable, non-exclusive licence to use the Service, not ownership of it.

Rights in video content and the original subtitles belong to their respective owners. The Service merely helps you display and process that content while you browse; it does not change who owns it, and it grants you no licence beyond what you already had.

12. Service changes and availability

• The Service is provided "as is". We work to keep it available but do not promise it will be uninterrupted or error-free.
• If the platforms we depend on (site APIs, AI models, payment channels) change, some features may be limited or temporarily unavailable. For example, AI subtitles currently don't work on YouTube.
• We may add, modify or discontinue features. If we discontinue a core feature you have paid for, we refund the corresponding amount pro rata.

13. Termination

You may stop using the Service at any time and cancel your subscription in the extension or through Paddle. If you seriously breach these terms, we may suspend or terminate your account after notice; where a paid period is involved, we refund the unused portion.

14. Disclaimers and limitation of liability

To the maximum extent permitted by applicable law, we are not liable for indirect losses, lost profits, lost data, or decisions you make in reliance on AI output. For any subscription period, our aggregate liability to you will not exceed the fees you actually paid for that period.

This clause does not exclude liability that cannot lawfully be excluded, including losses caused by our wilful misconduct or gross negligence, or consumer rights that the law of your jurisdiction makes non-waivable.

15. Governing law and disputes

These terms are governed by and construed in accordance with the laws of the People's Republic of China. But that does not mean you can only resolve a dispute in a Chinese court, and it does not affect mandatory provisions of the law in your own country or region that cannot be excluded by agreement — consumer protection rules in particular.

Specifically:

• If you are an individual consumer in mainland China: disputes arising from these terms should first be discussed in good faith; if that fails, either party may bring proceedings before a court of competent jurisdiction.
• If you are in the EU, the EEA, the UK or Switzerland: you keep all rights granted by mandatory local consumer protection law, and you may bring proceedings against us in the courts of your place of habitual residence. EU consumers also have the statutory 14-day right of withdrawal.
• If you are in Australia, New Zealand, Canada (including Quebec) or similar jurisdictions: consumer guarantees and remedies under local law are unaffected by these terms and cannot be excluded.
• Elsewhere: if local law gives you stronger protection than these terms, local law prevails.

Wherever you are, we'd ask you to write to support@livesubtitle.app first. The overwhelming majority of issues get resolved in conversation, and that's how we'd prefer to resolve them rather than through legal proceedings.

This clause does not affect your right to complain to a consumer protection or data protection authority in your country or region.

Note also that the payment transaction itself is completed with Paddle as seller. Disputes directly concerning payment, billing or taxes are therefore also subject to Paddle's own terms and processes.

16. Changes to these terms

If these terms change materially, we will update this page and its "last updated" date, and tell you by email or an in-product notice. Continuing to use the Service after a change means you accept the new terms; if you don't, you can stop using the Service and cancel your subscription before the change takes effect.

17. Contact

Questions about these terms: support@livesubtitle.app. We usually reply within 1–2 business days.