> For the complete documentation index, see [llms.txt](https://manual.trancy.org/en/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://manual.trancy.org/en/get-started/use-extension/bilingual-subtitles.md).
# Bilingual subtitles
Bilingual subtitles show two languages at once on the video you're watching — the original language and your native language stacked together — so you can follow along and learn from real content. Trancy adds bilingual subtitles on 8 supported platforms by using each platform's existing captions and translating them in real time.
#### This is different from AI Subtitle 2.0. When a YouTube video has no usable captions, AI Subtitle generates them from the audio using Whisper transcription — and that feature is YouTube-only. In short: bilingual subtitles translate captions that already exist across all 8 platforms, while AI Subtitle creates captions from scratch and works on YouTube alone
### How to turn on bilingual subtitles
1. Click the Trancy icon in the player control bar of each platform. If the icon does not show up, try refreshing the playback page.
2. Launch with keyboard shortcut `CMD/Ctrl + E`. If the default shortcut is not supported, you can refer to the video for manual configuration.
### Supported platforms
| Platform | Availability | Notes |
| -------- | ------------------ | ------------------------------------------------------------------------ |
| YouTube | Desktop and mobile | Bilingual subtitles plus AI Subtitle 2.0; the main video focus on mobile |
| Netflix | Desktop | Bilingual subtitles |
| Disney+ | Desktop | Bilingual subtitles |
| Udemy | Desktop | Course subtitles |
| Coursera | Desktop | Course subtitles |
| TED | Desktop | Bilingual subtitles |
| edX | Desktop | Course subtitles |
| HBO Max | Desktop | Bilingual subtitles |
{% embed url="" %}
Bilingual subtitles in action on a few supported platforms:
#### Youtube
#### Coursera
#### Udemy
#### **Netflix**
### AI Subtitle 2.0 (Premium)
AI Subtitle 2.0 creates accurate subtitles for YouTube videos that don't have good captions. Instead of relying on existing captions, it transcribes the video's audio with OpenAI's Whisper speech-to-text model, then adds Trancy's bilingual translation on top. Per Trancy's pricing comparison, AI Subtitle is a Premium feature.
#### How AI Subtitle works
1. Open a YouTube video and click the AI subtitle icon in the player control bar to add the video to the AI processing queue.
2. Wait for processing. AI subtitles usually take about 2-5 minutes; you can keep watching the video while it runs.
3. When processing finishes, the original captions are automatically replaced with the new AI-generated bilingual subtitles.
#### Good to know
* YouTube only. AI Subtitle works on YouTube and not on other platforms. Trancy's reasoning is that platforms like Netflix already provide good-quality official subtitles, so AI transcription isn't needed there.
* More accurate segmentation. Trancy reports roughly 80% better sentence segmentation than YouTube's own machine-generated captions, which makes the translated subtitles easier to read.
* Daily limit. Per Trancy's pricing comparison, Premium covers up to 40 AI-transcribed videos per day, and Premium + Advanced AI raises this to 60 per day.
* Shared, cached subtitles. Once a video has been processed, Trancy caches the result so other users can reuse it. A popular video may already have AI subtitles ready instantly.
* Beta feature. AI Subtitle 2.0 is still in beta, so quotas and behavior may change over time.
Note: Trancy's pricing comparison lists the AI subtitle limit as a per-video daily count (40/day on Premium, 60/day on Premium + Advanced AI). The standalone AI Subtitle page's FAQ still states a "5 hours per day" test-phase limit; this appears to be legacy copy, and the per-video daily count is the current figure. EDITOR TODO: confirm the live in-product quota and ask Trancy to update the /ai-subtitle FAQ so the two surfaces agree.
### Frequently asked questions
**Which platforms support bilingual subtitles?**
Trancy adds bilingual subtitles on 8 platforms on desktop: YouTube, Netflix, Disney+, Udemy, Coursera, TED, edX, and HBO Max. On mobile, video learning is currently focused on YouTube.
**What is the difference between bilingual subtitles and AI Subtitle?**
Bilingual subtitles translate captions that a platform already provides, and work on all 8 supported platforms. AI Subtitle generates captions from the audio using Whisper when a YouTube video has no usable captions, and works on YouTube only.
**Is AI Subtitle free?**
No. Per Trancy's pricing comparison, AI Subtitle is a Premium feature, with a daily video quota that increases on Premium + Advanced AI. Bilingual subtitles on existing captions are available on the free tier.
**Why do I have to wait for AI subtitles instead of getting them in real time?**
Transcribing audio with Whisper is processed asynchronously on Trancy's servers, so it usually takes about 2-5 minutes. Once a video is processed, the result is cached, so it can load instantly for the next person who watches it.
**How do I change the subtitle languages or display?**
Open the Trancy settings from the player control bar to choose your target language and adjust how subtitles appear. For a focused study layout, try [Theater mode, ](/en/get-started/use-extension/bilingual-subtitles/theater-mode.md)[Read mode, ](/en/get-started/use-extension/bilingual-subtitles/read-mode.md)or [Practice Mode](/en/get-started/use-extension/bilingual-subtitles/practice-mode.md).
*Last updated: June 5, 2026.*
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