Free. MIT OpenCourseWare (OCW) publishes complete lecture series from MIT professors on YouTube — open to anyone, no account required. If you want to study offline, downloading those videos is straightforward.
Why Download Instead of Streaming?
MIT lectures run 50–90 minutes each. Streaming them repeatedly on mobile data is expensive and fragile. Download once, watch as many times as you need — no buffering, no data cost.
How to Download MIT OCW Lectures
Step 1: Find the course playlist on YouTube — e.g. "MIT 6.006 Introduction to Algorithms".
Step 2: Open the lecture you want, copy the link.
Step 3: Paste into klypio.com/tools/youtube-downloader.
Step 4: Choose resolution (720p is usually sufficient for lecture slides), click download. The MP4 saves to your device.
Downloading Multiple Lectures
For a whole course, send links one by one to @KlypioBot on Telegram — the bot returns each file without you needing to open a browser tab per video.
Is This Allowed?
MIT OCW releases its materials under Creative Commons licenses. Downloading for personal study is consistent with those terms.
Start studying offline: klypio.com/tools/youtube-downloader
See also: Save Coursera lectures offline, Download freeCodeCamp lessons.