These two tools get compared constantly because they overlap on the surface — both put interactive dual subtitles on Netflix and YouTube — but they're built for different learners, and the honest comparison is about which learner you are.
What Language Reactor does better.
It's free to start, and the free tier is real: dual subtitles, pop-up dictionary, and precise playback controls on Netflix and YouTube without paying anything. Pro ($5.95/month or $39.95/year) adds speech-recognition subtitles and machine translation on Netflix, full word saving, and Anki export of saved words. It's polished, familiar (2M+ users by its own count), and there's essentially nothing to learn — install it and it works. It also reaches beyond video: podcasts, imported books and webpages with text-to-speech.
What Migaku does better.
Migaku is built around one conviction: that serious learners live in Anki. Its integration goes deeper than exporting saved words — it's designed for full sentence-mining workflows with rich cards, and it adds the Japanese-specific tooling that made its reputation: pitch accent display, furigana handling, and morpheme-level analysis that knows which words in a subtitle you've already learned. It also handles local video files, which neither Language Reactor nor most competitors touch — if your immersion library is downloaded content with subtitle files, Migaku serves it natively. Pricing runs ~$11/month (~$9/month billed yearly, ~$399 lifetime that cycles on sale); there's no free tier — a 14-day money-back guarantee instead.
The honest catches on each.
Language Reactor's ceiling: two video platforms, word-level (not workflow-level) Anki export, and no serious tooling for pitch accent or tones. Migaku's tax: the learning curve is real — it assumes you know what sentence mining is and want to configure it — and at no point is any of it free to try beyond the refund window.
Where neither wins.
If your dealbreaker is platform breadth (Disney+, Viki, Prime), both lose to LangPanda (20+ sites, built-in SRS and Anki export — a middle path between these two philosophies at $8.88/month). If it's budget, both lose to Trancy's free tier. Those four together are the real decision space: Best Subtitle Tools.
Verdict by learner type.
Casual-to-intermediate learner on Netflix/YouTube: Language Reactor free, upgrade to Pro only when you start saving words seriously. Committed Japanese learner with an Anki habit: Migaku is the specialist tool that respects your workflow. Anki-curious but not Anki-committed: LangPanda's automatic capture with both built-in SRS and Anki export is the friendlier version of Migaku's promise.