# LanguageShadow

> Free Chrome extension for language learners who practice on YouTube with dual subtitles, line-by-line shadowing pauses, and AI pronunciation scoring across 33 languages and regional voices.

## What it is

LanguageShadow is a free Chrome browser extension (Manifest V3). It runs on YouTube watch pages — not a standalone app. Learners shadow lines out loud and get AI feedback on accuracy, fluency, completeness, and prosody where supported.

## Who it is for

- People learning languages using YouTube immersion
- Shadowing / repeat-after-me practice on real video content
- Learners who want pronunciation scores per line, not only passive watching

## Key features

- Dual-language subtitles on YouTube (original + translation simultaneously)
- Line-by-line shadowing with auto-pauses and repeats
- AI pronunciation scoring and word-level feedback (powered by Azure Speech)
- Optional Google Sign-In for account sync and Pro subscription (not required to install or browse this site)

## Supported languages and regional voices (33 total)

English (US/UK/AU/CA/IN), Spanish (Spain/Mexico), French (France/Canada), Portuguese (Brazil/Portugal), Chinese (Mandarin/Cantonese/Taiwan), Arabic (Egypt/Saudi Arabia), German, Italian, Dutch, Russian, Polish, Swedish, Norwegian, Danish, Finnish, Japanese, Korean, Vietnamese, Thai, Malay, Hindi, Tamil, Catalan.

## Pricing

- **Free** — Dual subtitles, shadowing, and a daily allowance of AI pronunciation grades. No credit card required.
- **Pro** — $7.99 / month — 1,000 AI grades per month, no daily limits.

## Platform support

- Works on **desktop Chrome** (Windows, macOS, Linux, ChromeOS).
- Does **not** work on mobile — Chrome on Android and Safari on iOS do not support extensions.

## Frequently asked

**Is sign-in required?**
No. Browse YouTube, get dual subtitles, and shadow lines without signing in. Optional Google Sign-In syncs settings across devices and is required only to subscribe to Pro.

**Does it access my YouTube account?**
No. The extension reads the subtitle track of the video currently in view. It does not access your YouTube account, history, subscriptions, or any Google data beyond your email and user ID if you choose to sign in.

**Is data sent to third parties?**
Audio sent to Azure Speech for pronunciation scoring; nothing else leaves your device. Full details in the privacy policy.

## Links

- Website: https://languageshadow.com/
- Chrome Web Store: https://chrome.google.com/webstore/detail/oeekfbhfclncdmajhpjogmmcceabpnnf
- Privacy Policy: https://languageshadow.com/privacy
- Terms of Service: https://languageshadow.com/terms
- Support: support@languageshadow.com

## Google user data (OAuth)

If the user signs in: Google account email and user ID via Supabase OAuth — for account creation, settings sync, and billing only. The extension does not access the user's YouTube account through Google Sign-In.