Kostenloser Spaced Repetition Rechner

Berechnen Sie optimal spaced repetition review intervals. Maximize long-term memory retention mit scientifically proven timing.

Days before first review

Multiplier for interval growth (2.5 is standard)

Which review iteration to calculate

Next Interval (days)

16

Total Days Since First Study25
Next Interval (weeks)2.3

Next Interval (days) vs Initial Interval (days)

Formel

How Spaced Repetition Works

Spaced repetition increases review intervals over time as material is learned.

Formula

Next Interval = Initial Interval x Ease Factor ^ (Review Number - 1)

The ease factor determines how quickly intervals grow. Standard is 2.5, meaning each interval is 2.5x the previous one.

Typical Schedule

  • Review 1: Day 1
  • Review 2: Day 2–3
  • Review 3: Day 6–7
  • Review 4: Day 15–16
  • Lösungsbeispiel

    Starting with a 1-day interval and ease factor 2.5, calculating the 4th review.

    1. 01Next interval = round(1 x 2.5^3) = round(15.625) = 16 days
    2. 02Review 1: 1 day, Review 2: 2.5 days, Review 3: 6.25 days, Review 4: 15.6 days
    3. 03Total days elapsed ≈ round(1 x (2.5^4 - 1) / 1.5) = round(25.4) = 25 days

    Häufig Gestellte Fragen

    What is the ideal ease factor?

    The default 2.5 works well for most material. Reduce to 2.0 for difficult cards or increase to 3.0 for easy material.

    What apps use spaced repetition?

    Anki, SuperMemo, Quizlet (partially), and Memrise all implement spaced repetition algorithms.

    How does spaced repetition compare to cramming?

    Spaced repetition leads to much better long-term retention. Cramming may work for a test the next day but leads to rapid forgetting.

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