AI platform for non-beginners

Master your English with Subtlex AI

Learn English effectively through your favorite  content
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It’s like if ChatGPT and Duolingo had a baby

1. Choose your goal and bring content

ChatGPT makes answers, Subtlex builds your English. Paste a video with subtitles, an article, or a document and start learning the English you actually need
Choose your goal
Everyday ConversationsTech & IT EnglishMovies, Music & GamesBusiness EnglishTOEFL/IELTSTravel EnglishStudy Abroad
Speak confidently on trips and vacations
Here’s what you can upload to reach your goal
Travel Blogs
Upload travel blogs, tips, or destination guides (e.g., The Blonde Abroad, Nomadic Matt).
Tourism Websites
Upload city guides or tourist attraction information (e.g., Lonely Planet, Visit California).
YouTube Travel Channels
Upload videos from popular travel YouTube channels (e.g., Drew Binsky, Kara and Nate).
Travel Forums (Q&A)
Upload discussions, advice, or reviews from online travel communities (e.g., TripAdvisor, Reddit’s r/travel).
Enhance your technical English for IT and programming
Here’s what you can upload to reach your goal
Technical Documentation
Upload docs from MDN, Python Docs, or React Docs.
GitHub Discussions & Issues
Upload conversations from open-source repositories to learn real-world technical discussions.
Tech Blogs & Articles
Upload articles from Medium, Smashing Magazine, or Dev.to.
Conference Talks & Transcripts
Upload talks from Google I/O, WWDC, or TED Talks on technology.
Stack Overflow Threads
Upload Q&A discussions to learn problem-solving vocabulary.
Master English for university & research
Here’s what you can upload to reach your goal
Academic Textbooks
Upload university textbooks (e.g., "Psychology," "Economics").
Study Abroad Blogs
Upload tips from study abroad blogs (e.g., Study Abroad Blog, The Culture Trip).
University Resources
Upload guides for international students (e.g., Harvard College, Study in the UK).
YouTube Vlogs
Upload study abroad vlogs (e.g., The Abroad Experience, Global Study Adventures).
Expat Forums
Upload forum discussions for students abroad (e.g., r/StudyAbroad, ExpatForum).
Speak naturally in real-life situations
Here’s what you can upload to reach your goal
Casual Conversations
Upload conversations from online forums or articles (e.g., Reddit’s r/conversation, Quora).
TV Shows & Sitcoms
Upload transcripts or subtitles from popular TV shows (e.g., Subscene, OpenSubtitles).
Podcasts & Interviews
Upload transcripts from conversational podcasts (e.g., NPR, The Guardian’s "Podcasts").
YouTube Channels
Upload vlogs or casual YouTube content (e.g., Casey Neistat, The Financial Diet).
Ace TOEFL, IELTS, and other language tests
Here’s what you can upload to reach your goal
TOEFL/IELTS Preparation Blogs
Upload tips and strategies from TOEFL/IELTS preparation blogs (e.g., Magoosh, IELTS Liz).
Practice Tests & Exercises
Upload practice questions and test materials (e.g., TOEFL Practice Online, IELTS.org).
Study Guides & Books
Upload official TOEFL/IELTS study guides (e.g., "The Official Guide to the TOEFL Test," "Target Band 7").
YouTube IELTS/TOEFL Channels
Upload videos from channels focused on test preparation (e.g., IELTS Official, Magoosh TOEFL).
Academic Listening & Reading
Upload reading practice from TOEFL/IELTS style tests (e.g., TED Talks, BBC Learning English).
Communicate like a pro in international workplaces
Here’s what you can upload to reach your goal
Corporate Websites
Upload content from corporate websites (e.g., Forbes, Harvard Business Review).
Business News Websites
Upload articles from free business news sites (e.g., BBC Business, Reuters).
YouTube Business Channels
Upload videos from business-focused YouTube channels (e.g., TEDx Talks, The Economist).
Business Podcasts
Upload episodes from free business podcasts (e.g., The Tim Ferriss Show, HBR IdeaCast).
Enjoy movies, music, and games in English
Here’s what you can upload to reach your goal
Movie Scripts & Subtitles
Upload movie scripts, subtitles, or TV show scripts (e.g., Subscene, OpenSubtitles).
Music Lyrics
Upload song lyrics to learn language through music (e.g., Genius, AZLyrics).
YouTube Bloggers or Interviews
Upload interviews or YouTube videos about movies and music (e.g., The Take, Nardwuar).
YouTube Gameplays
Upload gameplays from YouTube channels (e.g., PewDiePie, Markiplier).

2. Get AI lessons and learn English effectively

Get Duolingo-like lessons, but with your content and the AI-powered features
Choose words and phrases you don't know
Subtlex analyzes your content and finds the most useful words and phrases

AI teaches you based on your level
The most common words learning process
Do exercises
Easy, medium, and hard exercises – complete them all to remember better

Subtlex reminds you when it's time to review words and phrases
Reviewing words with spaced repetition
Read any content like a book
Tap on words to see meanings, translations, pronunciations, and more

AI marks new and learned words in texts
AI-powered reading process

Who am I?

Developer phoneX (Twitter)TikTok
I'm Leven, a former corporate full-stack engineer and team lead, now a solo developer building Subtlex — a tool to learn English through real content.

I love learning languages, and I was frustrated by most language learning apps. They are mainly aimed at beginners, and it's very hard to reach any level above B1.

They never let you explore vocabulary from a newly released movie like Oppenheimer (where you understand maybe 10% but want to improve that). They don't let you read your newly bought book in its original language, and they limit you to a restricted, copyright-bound catalog. They don't allow you to learn vocabulary from your favorite game — something I wanted while playing The Last of Us.

These frustrations led me to create Subtlex :)

I wanted a way to actually learn English from the content I care about.

I hope you'll enjoy my app, and I'd be happy to hear any feedback, suggestions, or questions you might have.