The Leitner System — aka, the most efficient way to use flashcards.
Spaced repetition, active recall, flashcards … put them all together and you get the Leitner System.
The Leitner System is a technique for organizing flashcards that prioritizes studying more challenging material more often — until it becomes easy.
The Leitner System: How it Works
- Group your flashcards into different categories (i.e. boxes) based on the difficulty level
- Revisit the flashcards in the more difficult boxes more often than the easier ones
Read more: Check out our guide to Study Strategies.
Example way to set it up:
- Take 3 boxes and label them: Easy, Medium, Hard
- Every card starts in the Hard box
- As cards become easier to answer, “promote” them into the Medium or Easy boxes. If you find cards are still challenging, move them back one difficulty level.
- Review the cards in the Hard box 3 times a week, Medium box 2 times a week, and Easy box once a week
Variations on the Leitner System
So long as you keep the basic principles of the Leitner System, you can customize it to work best for you.
For example, to introduce more levels of difficulty, use more boxes. We recommend no more than 5, otherwise it can get too complicated.
Read more: Check out our guide to Digital Planner stickers.
Quick tips to simplify the Leitner system:
- Just use two boxes: hard and easy. The principle is the same: study the harder cards more often, and the easy ones less often. Depending on how you study, you may not need so many boxes.
- Use digital flashcards. The set up can be a hassle. Flashcards made in GoodNotes, for example, already employ the Leitner System in the background. They show you harder cards more often, and suggest a later study date to review them again.
Why the Leitner System Works
Introduced by German science journalist Sebastian Leitner, his system for committing information to memory incorporates some of the strongest memory techniques:
Flashcards themselves are one of the best ways to apply active recall when studying. When you work through the challenge of trying to remember something you’ve once learned, this is called active recall (also called retrieval practice). The process of doing so helps build pathways in your brain so it’s easier to find that answer in the future.
However, it’s all too easy to cram a study session in with too many rounds of the same flashcards. At a certain point, you reach a point of diminishing returns, where each additional round becomes less and less helpful.
That’s why the Leitner system calls for reviewing your cards once in several recurring sessions. This is called spaced repetition.
In this way, each time you revise, you’ve taken a break from the material (thus forgetting some of it) and need to work to actively recall it back again.
Lastly, you spend more time studying the material you’re unfamiliar with. By separating the “easy” and “challenging” material and studying them differently, it allows you to use your time more efficiently.