Review algorithms
What is FSRS?
FSRS, or Free Spaced Repetition Scheduler, is an open review scheduling algorithm. It is not a separate learning method, but a way to calculate when a card should return.
Shortest definition
FSRS helps an SRS choose the interval between reviews based on how difficult the card was and how stable the memory trace appears to be. Hard cards return sooner, easier cards less often.
How does it work in practice?
After you answer a flashcard, the algorithm updates its memory estimate for that card. It considers whether the answer was easy, hard, or wrong, then schedules the next encounter with the material.
In a well-designed system, FSRS does not replace active recall. It only helps decide when to ask you to recall again.
FSRS and spaced repetition
Spaced repetition is the general method of spacing reviews over time. FSRS is one way to schedule those intervals. Good results still depend on flashcard quality, consistency, and whether you genuinely try to recall the answer.
What does this mean in RevoMemo?
RevoMemo bases its review schedule on the open FSRS model and public Open Spaced Repetition benchmarks. This is not a promise of a specific result for every person, but a technical foundation for better review scheduling.
That is why FSRS works here together with learning vocabulary in context, sentences, and answer grading, not as a standalone shortcut to memorization.
Questions and answers
Do FSRS and SRS mean the same thing?
No. SRS is the general category of spaced review systems. FSRS is a specific algorithm that can power such a system.
Is FSRS enough to remember a word?
No. The algorithm schedules when a card returns, but memorization still requires a good flashcard, an attempt to recall, and contact with the word in a meaningful context.
Is FSRS closed RevoMemo technology?
No. FSRS is developed as an open review scheduler. RevoMemo uses this approach as part of its own learning experience.
Further reading
If you want to see a broader scientific basis for RevoMemo, go to the Research page. You’ll find there a discussion of spaced repetition, active recall, contextual learning, and spaced repetition scheduling algorithms.
Learn these rules in practice
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