Understanding the Leitner System— Fast & Free.
The classic "shoebox" method that revolutionized learning. See how it works and why digital algorithms are even better.
"Study smarter with Masterly AI"
Why choose Masterly?
Everything you need to study smarter.
Box Method
Cards move to higher boxes when answered correctly.
Self-Correction
Incorrect cards return to Box 1, ensuring mastery.
Visual Progress
See your knowledge grow as cards move up the chain.
Digital Upgrade
Masterly automates this process so you don't need physical boxes.
How it works
Three simple steps to mastery.
Box 1: Every Day
New and difficult cards that need constant review
Box 2: Every 3 Days
Cards you know reasonably well
Box 3: Weekly
Cards you have mastered and just need maintenance
Common Questions
Who invented the Leitner System?
It was proposed by German science journalist Sebastian Leitner in the 1970s.
Do I need physical boxes?
Traditionally yes, but apps like Masterly simulate this system digitally, which is much more efficient and portable.
What happens if I get a card wrong in Box 3?
In the strict Leitner system, it goes all the way back to Box 1. This penalty ensures you strictly main mastery.
Is FSRS different from Leitner?
Yes. Leitner is a rough approximation using fixed intervals (boxes). FSRS is a mathematical model that calculates precise review times based on your unique memory strength.
What is the algorithm used for spaced repetition?
We use the modern FSRS (Free Spaced Repetition Scheduler) algorithm, which is proven to be more efficient and accurate than the older SM-2 algorithm used by many other apps.
How does the AI generate flashcards and quizzes?
Our advanced AI analyzes your study materials (PDFs, notes, or lectures), identifies key concepts, definitions, and high-yield facts, and transforms them into interactive study cards and practice questions optimized for your exams.