Twinsubs
Language Reactor alternative for Mac: bilingual subtitles made on your own Mac
Language Reactor is a Chrome extension for learning languages from Netflix and YouTube, and its strengths are word lookup, a dictionary and study tools on top of dual subtitles. Twinsubs is a Mac app that turns any video or audio file into a bilingual SRT. To study a language while streaming, choose Language Reactor; to get a subtitle file or translate a local video, choose Twinsubs.
Where they differ
| Item | Twinsubs | Language Reactor |
|---|---|---|
| Form | Mac app (on the Mac App Store) | Chrome extension, desktop browsers only |
| Where it runs | On your Mac, nothing uploaded | Not verified |
| Price | Free for the first 10 minutes of each video and 10 minutes of live translation per day; one-time purchase removes the limits | A Pro mode exists, price: not verified |
| Bilingual subtitles | Yes, translation above the original (order can be swapped) | Yes (dual subtitles on streaming sites and YouTube) |
| Live translation | Yes, the sound playing on your Mac; works offline once the language packs are downloaded | No (not on the page) |
| Export SRT | Yes, a bilingual file and a target-only file | Not verified (not on the page) |
“Not verified” means the official page has no clear statement, or the answer sits in dynamic content we could not read; it does not mean the feature is missing. We did not sign up for any account or try any paid feature.
When to choose Language Reactor
- You are studying a language. The page describes looking up words as you watch, plus a dictionary and an AI chat feature.
- You want a tool many people use. The site says 2,000,000+ users.
- You only want dual subtitles on Netflix or YouTube. Install the extension and go, with no subtitle file needed.
When to choose Twinsubs
- You have a local video or recording. Language Reactor targets online platforms, while Twinsubs works on files on your disk.
- You need a subtitle file for an editor. Twinsubs outputs standard SRT.
- You want to translate sound from any app on your Mac, because Twinsubs listens to everything the Mac plays.
Limits of Twinsubs, stated up front
- System requirement: macOS 26 or later, Apple silicon.
- It outputs SRT only: no subtitle burn-in, no built-in editor, no speaker separation, no ASS, and it cannot import an existing SRT and translate it.
- Machine recognition and translation make mistakes; with heavy accents, loud music or many specialist terms, check the result against the video.
- Which language pairs work depends on Apple's on-device translation; there are 12 source languages and 20 target languages.
Moving from Language Reactor
The two do different jobs, so this is a division of labour rather than a migration: use Language Reactor when you study on Netflix or YouTube, and Twinsubs when you have your own videos or recordings and want a bilingual SRT. To keep material for review, drop the video into Twinsubs and load the resulting SRT in a player.
A few notes
Language Reactor's home page gives a feature overview but no clear statement about price, Pro mode details, where processing happens or subtitle export, so those cells are marked not verified. The page notes that it used to be called Language Learning with Netflix.
How to check this yourself
- Read the other product's pricing pagePrices, plans and free allowances change; trust the page on the day you buy.
- Run the same clip through bothPick a clip with an accent and some technical terms; it tells you more than a spec sheet. The free version of Twinsubs covers the first 10 minutes of each video.
- Check the export formatConfirm you can export SRT and that your usual editor imports it without errors.
- Check where the data goesRead the other product's privacy policy to see whether video or audio is uploaded. Ours is the privacy policy.
Sources (verified 2026-10-16)
- Language Reactor website · 2026-10-16
“Not verified” means the official page has no clear statement, or the answer sits in dynamic content we could not read; it does not mean the feature is missing. We did not sign up for any account or try any paid feature.
FAQ
Can Language Reactor translate a local video?
The site presents it as a browser extension for Netflix, YouTube and similar sites, and does not mention local video files. Twinsubs is the one that processes video files on your disk.
Is Language Reactor free?
The site mentions a Pro mode but does not spell out where free ends and paid begins, so please check the official page.
How reliable is the information on this page?
Every fact carries an official source and a verification date (2026-10-16), and anything we could not find is marked not verified. Prices and features change, so check the other product's own site before you buy; if you spot a mistake, write to twinsub@gatheon.com and we will correct it after checking.
Updated 2026-10-23. Back to the Twinsubs home page