The Forgetting Curve
Hermann Ebbinghaus discovered that memories fade exponentially over time. Without review, we forget up to 80% of what we learn within days. Spaced repetition interrupts this forgetting process. Each time you review a concept, the forgetting curve flattens, and the memory lasts longer.
FSRS-5: The Modern Algorithm
While older apps use SM-2 (created in 1987), Flevro uses the Free Spaced Repetition Scheduler (FSRS-5). FSRS models memory across three dimensions: Difficulty, Stability, and Retrievability. This leads to scheduling that is vastly more accurate, reducing your workload by over 20% while maintaining the same retention target.
Targeted Retention Rates
FSRS allows you to choose your desired retention outcome—typically between 80% and 95%. If you choose 90%, Flevro mathematically guarantees to show you the card precisely when your likelihood of remembering it drops to 90%. This hyper-efficient timeline minimizes wasted study sessions.
Stop forgetting what you learn.
Join the students and polyglots using Flevro to master their subjects with scientific precision.
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