Five boxes. Two simple choices.
The Leitner system spaces out flashcard reviews using five boxes. Here is exactly what happens to a card from the moment you create it.
The five boxes
Box 1
Cards you have learned enter here. After three hours they become ready to review.
Box 2
Cards wait in a queue and become ready as newer cards move forward.
Box 3
Cards wait in a queue and become ready as newer cards move forward.
Box 4
Cards wait in a queue and become ready as newer cards move forward.
Box 5
The final box — one successful review completes the card.
What a daily review looks like
Each day the app surfaces cards that are ready in the review zone. You see the word or phrase, try to recall it, then reveal the translation and grade yourself. A correct answer promotes the card one box; a miss sends it back to Box 1.
Waiting cards stay in their box until they become Ready. When no box is ready, study some New cards or return later. Each box shows its own ready and waiting counts.
Why it beats re-reading a word list
Recall is the mechanism. Reading a list feels productive and teaches you to recognise words in order; retrieving a word from a blank prompt is what makes it available when you need it. Spacing those retrievals out means each one costs more effort — and effortful retrieval is what lasts.
The boxes handle the scheduling. You only decide whether you knew the word.
Common questions
- What is the Leitner system?
- A spaced-repetition method that sorts flashcards into five boxes. A card you answer correctly moves one box further out. A card you miss goes straight back to Box 1. The boxes do the scheduling for you.
- How does review timing work?
- New cards stay outside the boxes until you know them. They then enter Box 1 and become ready after three hours. Boxes 2–5 use a review queue: as you add and succeed with newer cards, older cards move into the ready zone. There are no fixed day intervals for every box.
- Why does a wrong answer reset a card to Box 1?
- Because a word you could not recall has not been learned yet, regardless of how many times you got it right before. Restarting the interval is what makes the system reliable rather than optimistic.
- How do I answer a card?
- Reveal the answer, then choose “I know it” or “I don’t know it”. In a box review, a known card moves forward one box; an unknown card returns to Box 1. During first learning, a known card enters Box 1 and an unknown card stays New.
- What happens after Box 5?
- A successful review in Box 5 marks the card as completed. It leaves the active queue but stays in your deck for reference.
- How many cards should I review each day?
- Whatever is ready, plus a few new ones. Sessions default to thirty cards, which takes about five minutes at ten seconds a card. Consistency matters far more than volume.
- Can I study any language pair?
- Yes. Choose the language you are learning and the language you understand. One person may study English → Farsi; another may study German → Dutch. The product is multilingual, not a single pair.
Try it on your own vocabulary
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