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Spaced Repetition System (Anki Method)

learning · easy · 15-30 minutes daily (reviews) + 20-40 minutes weekly (card creation)

What is Spaced Repetition System (Anki Method)?

Spaced repetition exploits the spacing effect discovered by Ebbinghaus (1885) — memories are strengthened more efficiently when review sessions are spaced at increasing intervals rather than massed together. Modern SRS algorithms (SM-2 in Anki) schedule each card at the optimal moment just before you would forget it, riding the forgetting curve. This activates hippocampal reconsolidation: each retrieval strengthens the memory trace and shifts it from hippocampal-dependent to neocortical (long-term) storage.

Is there evidence for it?

EVIDENCEstrong

How do you do Spaced Repetition System (Anki Method)?

  1. 1.Install Anki (free on desktop/Android, $25 on iOS — worth it). Create your first deck with 20 cards using the 'minimum information principle': each card should test ONE atomic fact. Bad card: 'Describe the Krebs cycle.' Good card: 'The Krebs cycle produces ___ GTP per turn.' (Answer: 1). Use cloze deletions (fill-in-the-blank) as the default card type.
  2. 2.Follow the 20-card rule: add no more than 20 new cards per day per deck. This seems slow but compounds exponentially — after 6 months you will have 3,600+ cards in rotation with daily reviews taking only 15-20 minutes. Adding too many cards too fast leads to 'review hell' where daily reviews become overwhelming.
  3. 3.Review every single day without exception. Anki shows you cards the algorithm predicts you are about to forget. When reviewing, genuinely attempt retrieval BEFORE flipping the card — passive recognition ('oh yeah, I knew that') does not trigger the same hippocampal consolidation as active recall. Grade yourself honestly: Again (forgot), Good (recalled with effort), Easy (instant recall).
  4. 4.For complex subjects, use the 'elaborative encoding' technique when creating cards: add context, mnemonics, or images to the card. Piotr Wozniak's research shows that cards with emotional or visual associations have 2-3x higher retention rates. Connect each new fact to something you already know well.
  5. 5.After 30 days, audit your deck: sort by 'lapses' (times you forgot). Cards with 5+ lapses need to be reformulated — they are poorly encoded. Split them into simpler sub-facts, add mnemonics, or create a 'chain' of prerequisite cards. The SRS is only as good as the cards you feed it.

How long does it take?

15-30 minutes daily (reviews) + 20-40 minutes weekly (card creation).

Is it hard to start?

easy.

Source: Ebbinghaus 1885 Memory; Wozniak & Gorzelanczyk 1994 (SM-2 algorithm); Karpicke & Roediger 2008 Science (testing effect); Gwern Branwen's comprehensive SRS review
spaced-repetition · memory · anki · forgetting-curve · hippocampus · long-term-memory · active-recall
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This is one entry from the library Shift matches against. It is general information, not advice about you, and nothing on this page came from anyone's conversation.