Loading page
Feature checklists make every tool look equivalent. This table leads with the three things that actually differ — what it costs you before it works, whether your files leave your device, and where the free version stops.
| Ankiapps.ankiweb.net | Exercismexercism.org | freeCodeCampfreecodecamp.org | Khan Academykhanacademy.org | |
|---|---|---|---|---|
| What it does | Schedules flashcard reviews for the day before you would have forgotten them | Practice exercises in 80-odd languages with free feedback from a human mentor | Teaches web development by making you write code in the browser from lesson one | Explains school maths and science one short video and one exercise at a time |
| What it costs you | Free accountFree to use, but you have to register before it will do the job. | Free accountFree to use, but you have to register before it will do the job. | Free accountFree to use, but you have to register before it will do the job. | Free accountFree to use, but you have to register before it will do the job. |
| Your files | Runs on their server | Runs on their server | Runs on their server | Runs on their server |
| Where it stops | The browser side only reviews and lightly edits — real deck building means the free desktop app, and the iPhone client is a one-off paid purchase. | Mentor requests are volunteer-staffed, so busy tracks can leave a submission waiting days for feedback. | You need a free account to save progress, and the certificates are portfolio evidence rather than accredited qualifications. | Watching is open but practice and progress tracking need a free account, and nothing here carries academic credit. |
| Best for |
|
|
|
|
| Category | Learning & Reference | Learning & Reference | Learning & Reference | Learning & Reference |
| Last checked | 2026-07-29 | 2026-07-29 | 2026-07-29 | 2026-07-29 |
| Open the site | Open | Open | Open | Open |
This comparison is in the address bar — copy the URL to send it to someone.