InterSub
Verified Oct 16, 2026 ActiveDual-language subtitles on Netflix, YouTube and course sites, with hover translation and a saved wordbook
Listed on EffectHub ·
Pricing
- Pricing model
- Freemium
- Paid options from
- $1.50 once
- Billing
- One-time purchase
The cheapest paid entry is a pay-as-you-go pack of word lookups starting at $1.50 as a one-off purchase (200, 500 or 1000 lookups), not a subscription. The recurring Premium plan with unlimited lookups starts at $6 a month; the free tier allows 15 lookups a month and a 14-day trial covers everything.
Use tool ↗About InterSub
InterSub is a browser extension that shows subtitles in your own language and the one you are learning at the same time, translates a word or phrase when you hover it, and files what you looked up into a wordbook you can drill later or push to Anki. It detects phrasal verbs and idioms rather than translating word by word, and can pause playback on each subtitle line. It runs on YouTube, Netflix, Prime Video, Crunchyroll, TED, Coursera, Udemy and LinkedIn Learning in Chrome, Edge and Firefox, across about 30 languages. Free accounts get 15 lookups a month, pay-as-you-go packs of lookups start at $1.50, and the unlimited Premium plan starts at $6 a month. Published by InterSub Inc. in New York.
- Platforms
- Web · Chrome extension
- API
- Not confirmed
- Last verified
- Oct 16, 2026
Verified sources
- Product page describing dual subtitles, hover translation, wordbook, supported platforms and browsers, and the InterSub Inc. New York addressintersub.cc ↗
- Plans and prices page listing the free 15-lookup tier, pay-as-you-go packs from $1.50 and Premium from $6 a monthintersub.cc ↗
Is InterSub legit?
We don’t label tools safe or unsafe. Below are the records we checked ourselves, each with the date we read it.
- Domain registered
- Mar 7, 2022 (4 years ago)Registry record (RDAP), registrar NameCheap, Inc., looked up Sep 6, 2026
- TLS certificate
- Issued by Let's Encrypt, valid until Jan 9, 2027Seen in our own connection to the site on Oct 16, 2026
- Last checked
- Oct 16, 2026The site answered
- Operated by
- InterSub Inc., United StatesOur research, card verified Aug 23, 2026
Pros & cons of InterSub
Does the one thing immersion learners actually want: two subtitle tracks at once, a hover translation that understands idioms, and every lookup saved somewhere you can revise it. Platform coverage stretches past streaming into Coursera, Udemy and LinkedIn Learning, which few rivals bother with. The metering is fiddly — lookups are counted, and the free allowance of 15 a month is token.
Pros
- Dual subtitles across 10+ platforms including Netflix, Prime Video, Crunchyroll and Coursera
- Hover translation detects phrasal verbs and idioms instead of single words
- Every lookup is saved to a wordbook that exports to Anki
- Chrome, Edge and Firefox support across roughly 30 languages
- Pay-as-you-go packs from $1.50 make trying it nearly free, and refunds run 14 days
Cons
- Free tier allows only 15 word lookups a month
- AI-translated dual subtitles need a paid plan; the free tier gets untranslated dual tracks only
- Vocabulary training on mobile apps and bots is limited outside the Premium plan
- The site is a Tilda page with an inconsistent link or two, which is not confidence-inspiring
Best for
- Learners watching Netflix or YouTube in a target language
- Students following Coursera or Udemy courses in a second language
- Anyone who already revises vocabulary in Anki
Not for
- People who want structured lessons rather than immersion
- Users who dislike per-lookup metering on a subscription
Watch out: Both the lookup counter and the plan tiers are worded loosely on the pricing page — check what a pack actually includes before buying, since packs and the subscription meter the same action differently.
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