🆓 Free · No API keys

Study Coursera
in Spanish,
hands free.

A browser extension that detects English subtitles on Coursera videos, translates them automatically and reads them aloud. Works on Chrome, Edge and Microsoft Surface.

🔊
A3B Voice Narrator
Coursera EN → ES · Surface Edition
v2.2.1
Narrador activo
Velocidad 1.2×
Machine learning finds patterns in data
El aprendizaje automático encuentra patrones en los datos
0€
Cost, forever
0
API keys required
6+
Browsers supported
6
Surface models optimized
180ms
Detection latency

Three steps. That's it.

01

Open a Coursera video

Navigate to any course on Coursera and enable the English subtitles using the CC button in the video player.

02

Click the 🔊 icon

Click the extension icon in your browser toolbar and press "Activate Narrator". That's all the setup needed.

03

Listen in Spanish

The extension detects each subtitle, translates it to Spanish and reads it aloud in real time as the video plays.

Everything you need,
nothing you don't.

Real-time translation

Subtitles are detected and translated instantly using Google Translate, with a 180ms debounce to avoid stuttering.

🔊

Native voice synthesis

Uses your browser's built-in Web Speech API. No external TTS service needed. Supports all system voices.

🧠

Smart voice selection

Automatically prioritizes high-quality Spanish voices: Microsoft Sabina, Raul, Helena on Windows; Mónica on Mac.

💾

Translation cache

Repeated subtitles are served from a local cache — no duplicate API calls, lower latency, works offline for cached text.

🛡️

Privacy first

Only subtitle text leaves your device — sent to Google Translate for translation. No personal data. No tracking.

📱

Cross-platform

Chrome, Edge, Firefox, Kiwi Browser (Android). A universal bookmarklet covers every other browser.

Built for Surface.

Surface Pro 11 ARM

Snapdragon X Plus / X Elite · 13" · 267 PPI · 120Hz

Native ARM64 support. LCD and OLED variants. High-DPI overlay at 267 PPI.

🏢

Surface Pro 11 Intel

Intel Core Ultra · Business · Feb 2025

Full compatibility for enterprise deployments. MSIX installable via Intune.

Surface Pro 12 ARM

Snapdragon X Plus 8-core · 12" · 220 PPI · Fanless

Fanless design — no background noise competing with the narrator. Wi-Fi 7.

💻

Surface Laptop 7

Snapdragon X Elite / Intel · 13.8" & 15"

Copilot+ PC compatible. Full support for Windows Hello and Edge extensions.

🎨

Surface Studio 2+

Intel + RTX 4060 · 28" · 4500×3000

Overlay automatically adapts to the 28" canvas. Large touch-friendly controls.

📋

Surface Hub 2S

Intel · 50" Touch · Teams Rooms

Hub-specific overlay layout. Perfect for language learning in meeting rooms.

Available everywhere.

🚀 Launch offer — 52% off Pro annual license · First 200 users only 00h 00m 00s Get the deal →

Simple, honest pricing.

Free
$0 / forever

Everything you need to start studying Coursera in Spanish today. No credit card, no account.

  • EN→ES real-time translation
  • Web Speech API narration
  • Chrome, Edge, Firefox, Kiwi
  • Microsoft Surface support
  • On-screen subtitle overlay
  • Speed, volume & pitch control
  • Community support (GitHub)
  • Personal use license
Download free
Common questions
Is the free version really free forever?

Yes. The free version includes all core functionality — translation, narration, Surface support, and all browsers. It will never be paywalled. Pro is for people who want extras and want to support development.

What happens when my annual license expires?

You keep using the free version without interruption. Pro features (priority support, DeepL, SRT export) become unavailable until you renew. No data is lost.

How does the license key work?

After payment, Stripe sends a receipt to your email with your license key. Enter it in the extension settings to unlock Pro features. One key works across all your devices.

What is the commercial use license?

The free version is for personal, non-commercial use. The Pro license allows use in a business context — for example, a company deploying the extension for employees learning English courses, or an educator using it in a classroom.

Is the launch price permanent?

No. The $11.99 launch price is available for the first 200 Pro subscribers only. After that, the price returns to $24.99/year. Current subscribers keep their price on renewal.

Which payment methods does Stripe accept?

Visa, Mastercard, American Express, Apple Pay, Google Pay, and local payment methods depending on your country. All payments are secured by Stripe.

Simple and honest.

✅ What leaves your device

Only the text of the video subtitles is sent to Google Translate for translation. This is the same text visible on your screen. No metadata, no account info, no URLs.

🚫 What we never collect

We do not collect, store or share any personal data, browsing history, course names, account information, or any data beyond what's strictly necessary for translation.

💾 Local storage only

Your preferences (voice, speed, volume) are saved locally in your browser using chrome.storage.local. This data never leaves your device.

📄 Full policy

Read the complete privacy policy on GitHub: PRIVACY.md →