Dual Subtitles for YouTube

Read Frog turns YouTube captions into bilingual subtitles, including Shorts and embedded players, and AI can transcribe videos that have no captions at all. Select any word in the subtitles to look it up and save it for review.

最終更新：2026年10月5日

Bilingual subtitles on any captioned video

With Read Frog installed, open a YouTube video that has captions and click the Read Frog button in the player's control bar. The captions become bilingual: the translation and the original line stacked together, in sync with the video.

Works on regular videos, Shorts, and YouTube players embedded on other sites.
Turn on Translate on open and every video starts translating as soon as it loads, without clicking the button.

AI subtitles for videos without captions

Plenty of talks, podcasts and tutorials have no captions, or only auto-captions full of misheard words. Read Frog can have AI transcribe the audio itself, then show the result as the same bilingual subtitles.

Transcription runs in the cloud, so your machine does no heavy lifting, and the spoken language is detected automatically.
It works on regular videos, Shorts, live replays and embedded players.
Pro includes 300 minutes a month; Ultra includes 1,000.

The Read Frog subtitle menu with Request AI subtitles highlighted

Subtitles the way you like them

Layout

Show the original only, the translation only, or both, with the translation above or below the original.

Style and position

Adjust the font, size, colors and background opacity, and drag the subtitles anywhere on the player. For effects beyond the controls, such as blurring the translation until you have listened once, write CSS with Custom Subtitle Styles.

Downloads

Download the original or the translated subtitles.

Smoother sentences, and the whole video at a glance

Sentences that read naturally

YouTube's auto-captions often split one sentence into several fragments. Turn on AI smart segmentation and Read Frog has an LLM regroup the fragments into whole sentences before translating them, so they read more smoothly. It needs an LLM provider.

The whole transcript, and an AI summary

Open Learning in the Read Frog menu and a panel opens on the right of the page, with two tabs:

Subtitles lists every line of the video with its timestamp and translation. Click a line to jump to that moment.
AI summary sums up the whole video, using the LLM you picked for video subtitles.

Learn while you watch

Words in the subtitles can be selected, looked up and saved. Select an unfamiliar word, have AI explain what it means and how it is used, and save it to Notebase in one click. Add a card template to the notebase and your notes become flashcards that FSRS schedules for review, so the time you spend watching builds a vocabulary list of your own.

Videos on X, too

On X (Twitter), captioned videos in a post, in the replies or in your timeline get the same bilingual subtitles in one click, with the same style settings as YouTube.

Your choice of translation service

Video subtitles have their own translation service, prompt and request rate, separate from page translation. Use the free Google or Microsoft translator, connect an LLM such as OpenAI, DeepSeek or Gemini, or run a local model with Ollama. See Set Up Providers and API Keys.

Getting started

Install Read Frog

Follow the installation guide.

Turn on subtitle translation

Open a YouTube video with captions, click the Read Frog button in the player's control bar, and turn on subtitle translation.

Make it yours

Adjust the display and style in Video Subtitles.

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