Translify is an AI reading companion for foreign-language books. You upload a PDF or EPUB, Translify rebuilds it in your language with the original layout intact, then lets you chat with the whole book, highlight passages for AI explanations, and quiz yourself on what you read.

How is Translify different from Google Translate or DeepL?

Google Translate and DeepL translate text and return a file. Translify gives you a complete reading experience around the translation: chat with the whole book, AI-explained highlights, quiz mode, and side-by-side bilingual reading. It is a study tool, not a translation utility.

Is there a free trial?

Yes — every paid plan starts with a 14-day free trial, no credit card required. Translify also offers a 30-day money-back guarantee on every paid plan, with no questions asked.

Which file types and languages does Translify support?

PDF and EPUB up to 200 MB per book. Translify supports 14 target languages: English, French, Spanish, German, Italian, Portuguese, Dutch, Arabic, Chinese, Japanese, Korean, Russian, Hindi, and Turkish — with correct rendering for right-to-left scripts and CJK characters.

Does the translation keep the book's layout?

Yes. Translify rebuilds every page with the same structure: paragraphs in the same place, images where they were, tables intact, headings preserved. A side-by-side mode lets you switch back to the source at any time.

How accurate are Translify's chat answers?

Every chat answer links back to the exact passage in the source — page number plus a highlighted excerpt. If a faithful citation cannot be found in the book, Translify says so rather than guessing. The underlying model is Anthropic's Claude.

Can I cancel any time?

Yes — one click in account settings. You keep access through the period you have already paid for, and Translify never auto-charges the day after cancellation.

Does Translify train AI models on my uploaded books?

No. Uploaded books are private to your account, encrypted at rest, and never used to train any AI model. You can delete a book and all its derivatives at any time from your library.

Can AI turn a YouTube video into study material?

Yes, if the video has captions. The captions are a timestamped transcript of everything said in the video. An AI reading tool can take that transcript, break it into searchable passages, and let you ask questions, generate quizzes, and jump to the exact moment a topic was covered. The quality depends entirely on the captions: a clear lecture with accurate captions produces excellent study material; a video with no captions or auto-captions full of errors produces poor material.

Do I need the video to have captions?

For caption-based tools, yes. Most educational YouTube content — university lectures, Khan Academy, CrashCourse, conference talks, MOOC mirrors — has either creator-provided captions or reasonably accurate auto-generated ones. If a video has no caption track at all, a captions-based tool can't build study material from it. You can usually tell by clicking the CC button in the YouTube player before importing.

Is it legal to use YouTube videos for studying like this?

Using a public video's captions to build private study notes for yourself is ordinary personal study, the same as taking notes while watching. The line to watch is redistribution: don't republish a creator's transcript or sell study material built from copyrighted lectures. For your own exam prep, you're on solid ground.

How is this different from just asking ChatGPT about a video?

A general chatbot doesn't have the video. If you paste a link it either can't open it or guesses from the title. A grounded study tool ingests the actual transcript, so its answers come from what was said in the video — and it can cite the timestamp, so you can verify and jump straight to that moment. That citation is the difference between a plausible guess and a checkable answer.

What kinds of videos work best?

Anything information-dense and spoken: lectures, recorded seminars, exam-review videos, documentary explainers, conference talks, tutorial walkthroughs. Music videos, vlogs, and highly visual content (where the meaning is on screen, not in the words) work less well, because captions only capture what's said, not what's shown.

Does watching at 2x speed plus AI actually save time?

It changes what you spend time on. Watching once at 1.5–2x to get the shape of the material, then using AI Q&A and a quiz to find and close your specific gaps, is far more efficient than re-watching a 90-minute lecture to find the five minutes you didn't understand. The time saving comes from never re-watching what you already know.

How to study from YouTube videos with AI (notes, quizzes, and timestamped answers)

YouTube is the largest collection of lectures, explainers, and seminars ever assembled, and one of the worst tools for actually studying them. You can watch, but you can't search what was said, can't test yourself, and can't find the ninety seconds that explained the thing you still don't understand without scrubbing the timeline and guessing. This is a practical workflow for turning a captioned YouTube video into study material you can question, quiz, and come back to.

Why YouTube is a bad study tool by default

Watching a lecture feels like studying. It mostly isn't. Three things are missing, and each maps to something we know about how learning actually works.

It's passive. Watching produces the illusion of understanding — the speaker is fluent, so the material feels clear. But recognition (this looks familiar) is not recall (I can produce this myself), and only recall predicts exam performance.
It isn't searchable. A textbook has an index and a contents page. A 90-minute video has a scrubber and your memory of roughly where the thing was. Finding a specific definition again means re-watching.
There's no feedback. You never find out what you missed until the exam. Reading or watching without ever testing yourself leaves your weak spots invisible.

Fixing this used to mean pausing constantly to take notes — which has its own cost (see our guide to taking notes from video lectures). AI changes the economics: the transcript becomes searchable text you can interrogate and quiz, without scrubbing or re-watching.

The workflow, step by step

1. Import the video

Paste the YouTube link into a reading tool that supports video import. Behind the scenes it pulls the video's caption track — the timestamped transcript of everything said — and turns it into a set of searchable passages, each tagged with the moment in the video it came from. This is why captions matter: no captions, no transcript, no study material.

In Translify, this is the same flow as uploading a book: paste the link from your library, and the video opens in a player with study tools beside it.

2. Watch once, actively

Watch the video through at a comfortable speed — 1.25–1.5x for a familiar topic, 1x for a hard one. The goal of the first pass is the shape of the argument, not mastery of every detail. Don't pause to transcribe; you'll fill gaps in the next step without losing the thread.

3. Ask questions and get timestamped answers

When something didn't land, ask. What did she mean by “regularization” here? Summarise the three causes of the 1929 crash he listed. Where does the proof use the assumption that the function is continuous? A grounded tool answers from the transcript and cites the timestamp, so you can click and jump straight to that moment in the video to hear it in the speaker's own words.

This is the part that replaces scrubbing. Instead of dragging the timeline hunting for “the bit about mitochondria,” you ask for it and get sent there. We go deeper on this in how to chat with a YouTube video using AI.

4. Quiz yourself

This is the step almost everyone skips and the one that matters most. Generate a short quiz from the video and take it. Retrieval practice — the act of pulling an answer out of your head rather than re-reading it — is one of the most robust findings in learning science. A five-question quiz after a lecture tells you in two minutes what an hour of re-watching wouldn't: which parts you actually own and which only felt familiar.

Recognition is not recall. If you can't answer a question about the video without re-watching it, you haven't learned it yet — you've just met it.

Which videos this works for

The method is only as good as the captions, and captions only capture what's spoken. That makes it excellent for:

University and conference lectures, and recorded seminars.
Exam-review and “explained” videos (the genre students already live in before exams).
MOOC content mirrored to YouTube — Khan Academy, CrashCourse, MIT OpenCourseWare, and similar.
Documentary-style explainers and tutorial walkthroughs.

It works poorly for anything where the meaning lives on screen rather than in the words — silent demonstrations, music, heavily visual design tutorials. The transcript can't see the screen.

Making it stick beyond one session

A single quiz is good; spaced practice is better. The same principle that powers vocabulary learning (see our reading-based language plan) applies to lecture content: revisit the material at widening intervals — a day later, three days, a week — and re-quiz each time. Because the video is now a searchable, questionable object rather than a 90-minute timeline, a “review” is five minutes of targeted Q&A on the parts you missed, not a re-watch.

Honest limits

No captions, no study material. If a video has no caption track, a captions-based tool can't help. Check the CC button before you import.

Auto-captions can be wrong. Auto-generated captions struggle with accents, technical jargon, and crosstalk. Answers inherit those errors. For high-stakes material, spot-check against the video — which is exactly why timestamped citations matter.

It doesn't replace watching. The tool helps you find and test, not skip. The understanding still comes from engaging with the material; AI just removes the busywork around it.

Translify turns a YouTube link into a study workspace — a player with transcript-grounded chat and auto-generated quizzes, answers that cite the timestamp. Free 14-day trial.

Frequently asked

Can AI turn a YouTube video into study material?: Yes, if the video has captions. The captions are a timestamped transcript of everything said in the video. An AI reading tool can take that transcript, break it into searchable passages, and let you ask questions, generate quizzes, and jump to the exact moment a topic was covered. The quality depends entirely on the captions: a clear lecture with accurate captions produces excellent study material; a video with no captions or auto-captions full of errors produces poor material.
Do I need the video to have captions?: For caption-based tools, yes. Most educational YouTube content — university lectures, Khan Academy, CrashCourse, conference talks, MOOC mirrors — has either creator-provided captions or reasonably accurate auto-generated ones. If a video has no caption track at all, a captions-based tool can't build study material from it. You can usually tell by clicking the CC button in the YouTube player before importing.
Is it legal to use YouTube videos for studying like this?: Using a public video's captions to build private study notes for yourself is ordinary personal study, the same as taking notes while watching. The line to watch is redistribution: don't republish a creator's transcript or sell study material built from copyrighted lectures. For your own exam prep, you're on solid ground.
How is this different from just asking ChatGPT about a video?: A general chatbot doesn't have the video. If you paste a link it either can't open it or guesses from the title. A grounded study tool ingests the actual transcript, so its answers come from what was said in the video — and it can cite the timestamp, so you can verify and jump straight to that moment. That citation is the difference between a plausible guess and a checkable answer.
What kinds of videos work best?: Anything information-dense and spoken: lectures, recorded seminars, exam-review videos, documentary explainers, conference talks, tutorial walkthroughs. Music videos, vlogs, and highly visual content (where the meaning is on screen, not in the words) work less well, because captions only capture what's said, not what's shown.
Does watching at 2x speed plus AI actually save time?: It changes what you spend time on. Watching once at 1.5–2x to get the shape of the material, then using AI Q&A and a quiz to find and close your specific gaps, is far more efficient than re-watching a 90-minute lecture to find the five minutes you didn't understand. The time saving comes from never re-watching what you already know.

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