Hello folks. I hope you are gonna have a fantastic weekend ahead, as I am bringing you a big update for Captionz! I’m launching Captionz‑ext, an ultra-lightweight browser extension that finally makes dual subtitles on YouTube practical. Thanks to auto‑translate, you can pair almost any language, do quick A‑B repeats, and add community notes, all while you watch.

As you know, dual subtitles have always been my goal. Finally they’re realistic for most videos, which means our second subtitle can finally show up 🙂
And the best part: Captionz is completely free. I first thought I’d need AI to translate captions (which would cost money), but YouTube already provides auto‑translate. I just enhance the experience and bring both subtitles together.

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Why This Is a Milestone

My goal is to help you learn from real videos, like movies, interviews, lectures, and news etc. without losing your flow. I built Captionz‑ext to make dual subtitles practical on most YouTube videos by adding auto‑translate when only one track exists. It also syncs with the Captionz web app for tools like A‑B repeat, notes, and search. Simple setup, more learning.

Free — No Fees

Early on, I planned to use AI to translate captions, which would have meant a paid “pro” plan. Thankfully, YouTube already has auto‑translate. Captionz‑ext simply connects the dots so you can see two subtitles at once. Enjoy Captionz completely free.

What’s New Auto‑translate: Turn it on to cover almost any language. If a video has only one caption track, auto‑translate adds the second. Dual subtitles: My core goal, now practical on most videos. See two languages at once. One‑click access: I added a “Watch on Captionz” button on YouTube video pages. Context menu: I added a right‑click menu to open any YouTube link in Captionz. Sync with Captionz: Captions flow into Captionz, so A‑B repeat, notes, and Dictionariez work right away.

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How It Works

I built Captionz‑ext to read the captions (and auto‑translated ones) on YouTube, then sync them with the Captionz web app. Many videos only include one auto‑generated track, auto‑translate provides the second. Pick your two languages and watch them side by side. No complicated setup, no secret switches.

A Brief History

Five years ago, I launched the first version of Captionz. My debut post on Reddit was a hit: “I made a site that helps you watch YouTube with dual subtitles”.

Back then, I didn’t need an extension. YouTube captions were public; you could request and download tracks, and Captionz could combine languages freely.

Later, YouTube restricted external caption requests. To keep things working, I added a handy button in Dictionariez so users could still open videos on Captionz with dual subtitles — at least for videos that had multiple tracks by default.

A few months ago, YouTube encrypted caption requests, which made access harder. I switched to a simple, privacy‑friendly approach with a lightweight extension and separated Captionz from Dictionariez. That keeps Dictionariez focused and gives Captionz users a stronger, dedicated tool.

And yes: I made Captionz‑ext free and open‑source. High‑fives all around.

Who It’s For Learners: Compare native + target language subtitles in real time to build comprehension and confidence. Teachers & Tutors: Use any YouTube video for bilingual instruction with A‑B looping and notes. Polyglots: Switch language pairs and auto‑translate to explore content across the world. Casual Viewers: Understand more, faster—without pausing to look things up. Quick Start Chrome: Install from the Chrome Web Store. Edge: Install from Microsoft Edge Add‑ons. Firefox: Firefox Add‑ons.

Open any YouTube video and click “Watch on Captionz.” Or right‑click a video link and choose “Open in Captionz.” Pick your two languages, turn on auto‑translate if needed, and you’re set. Your coffee can stay hot; setup is quick.

Manual Installation (Alternative) Download the source code from GitHub. Go to chrome://extensions/ in your browser. Enable Developer mode (top right). Click Load unpacked and select the extension folder. Privacy

I aim for minimal, respectful integration. Captionz‑ext only accesses captions needed to enable features and does not collect personal browsing history. Read the privacy policy for details and updates.

FAQs Do dual subtitles work on all videos? It depends on captions. Many videos have only one auto‑generated track; turn on auto‑translate to add the second language. Which languages are supported? Auto‑translate covers most languages YouTube supports. Dual subtitles work when two tracks exist or one is auto‑translated. Do I need the Captionz web app? The extension helps on YouTube and pairs with Captionz for A‑B repeat, notes, and more. Together is best. Does this work on Shorts? Not at the moment. Do you really want it to work on Shorts? Comment below to let me know. Is it free? Yes — and there are no AI translation fees. Auto‑translate is provided by YouTube; Captionz just enhances the experience. Call to Action

Install Captionz‑ext (it’s free) and try dual subtitles on your next video:

Chrome: Captionz – YouTube Dual Subtitles Edge: Captionz – YouTube Dual Subtitles Firefox: Captionz – YouTube Dual Subtitles.

Open a video you love, turn on auto‑translate to widen language coverage, and use A‑B repeat to nail tricky lines. Add a note or two to help the next learner (or future you).

TL;DR

Captionz + Captionz‑ext = dual subtitles on YouTube—made practical by auto‑translate—plus A‑B repeat and notes, across almost all languages. It’s completely free. Click “Watch on Captionz” and start learning faster. Smiles optional, progress guaranteed.

Hello everyone,

Just a few days after the major release of v7.0, I am back with another update! Dictionariez v7.1.0 is now available, and it is all about breaking language barriers.

🌍 4 New Languages Supported

I heard your feedback loud and clear. You wanted more languages, and I am delivering. This version adds native support for 4 new languages:

🇳🇱 Dutch 🇬🇷 Greek 🇮🇳 Hindi 🇮🇷 Persian (Farsi)

This means you can now double-click words in these languages to get instant definitions, pronunciations, and translations. For Persian, I have ensured full Right-to-Left (RTL) support for a seamless reading experience.

🎯 Smarter English Lookup

English is a language that loves to borrow words. Words like café, détente, naïve, or jalapeño are common in English texts but often tripped up the dictionary because of their accents.

In v7.1, I have improved the detection engine. Dictionariez now smartly recognizes these accented words as English when you are reading in an English context, ensuring you get the correct definition without switching languages manually.

📚 Better Definitions for Polyglots

For learners of German, Spanish, Italian, Japanese, and French, I have tweaked the engine to prioritize Wiktionary results. Previously, Google Dictionary provided definitions in the target language (e.g., German definitions for German words), which could be challenging for beginners. Wiktionary results often include definitions in English, making it much easier to understand the meaning while you are still mastering the language. Don't worry though, if Wiktionary comes up empty, it seamlessly falls back to Google Dictionary to ensure you always get a result.

🛠️ Robust & Reliable

I have also added a suite of new automated tests to ensure these new features work perfectly and don't break existing ones. This makes Dictionariez more stable and reliable than ever.

It's now already available on Firefox, and needs a few more days for review on Chrome webstore and Edge addons. Stay tuned!
Update to v7.1.0 asap and keep exploring the world of languages!

Happy Learning,
River