FSRS: A modern, efficient spaced repetition algorithm

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  1. fsrs4anki

    A modern Anki custom scheduling based on Free Spaced Repetition Scheduler algorithm

    the stability and when you last reviewed the card, and the stability will update a bit longer if you somehow managed to still recall a card after the due date.

    [0] https://dl.acm.org/doi/10.1145/3534678.3539081?cid=996605471...

    [1] https://github.com/open-spaced-repetition/fsrs4anki/wiki/The...

  2. Stream

    Stream - Scalable APIs for Chat, Feeds, Moderation, & Video. Stream helps developers build engaging apps that scale to millions with performant and flexible Chat, Feeds, Moderation, and Video APIs and SDKs powered by a global edge network and enterprise-grade infrastructure.

    Stream logo
  3. Anki-Android

    AnkiDroid: Anki flashcards on Android. Your secret trick to achieve superhuman information retention.

    Stable on AnkiMobile, available in the AnkiDroid 2.17 alpha:

    * https://github.com/ankidroid/Anki-Android/releases/ (Parallel.A)

    * OR: https://ankidroid.org/#alphaTesting

  4. srs-benchmark

    A benchmark for spaced repetition schedulers/algorithms

    I've shared it here in the original ticket that added the benchmark confidence intervals https://github.com/open-spaced-repetition/fsrs-benchmark/iss...

  5. simple-spaced-repetition

    Simple spaced repetition scheduler based on the classic Anki algorithm.

    Very interesting. According to the benchmarks, with this algorithm, users can review 20-30% fewer cards than with the classic Anki algorithm.

    Just a few days ago, I published a Python implementation of the classic SM-2 algorithm that I use for https://python.cards, but I may switch to FSRS. https://github.com/vlopezferrando/simple-spaced-repetition

  6. mnemosyne

    Mnemosyne: efficient learning with powerful digital flash-cards.

    I wonder if there is plan for this to land in Mnemosyne[1]. I prefer Mnemosyne over Anki because I can self-host the web-sync server.

    1: https://mnemosyne-proj.org/

  7. free-spaced-repetition-scheduler

    A spaced repetition algorithm based on DSR model

    Libraries: https://github.com/open-spaced-repetition/free-spaced-repeti...

    All are MIT licensed I believe, Anki is primarily AGPL

  8. Libraries: https://github.com/open-spaced-repetition/free-spaced-repeti...

    All are MIT licensed I believe, Anki is primarily AGPL

  9. InfluxDB

    InfluxDB – Built for High-Performance Time Series Workloads. InfluxDB 3 OSS is now GA. Transform, enrich, and act on time series data directly in the database. Automate critical tasks and eliminate the need to move data externally. Download now.

    InfluxDB logo
  10. ebisu

    Public-domain Python library for flashcard quiz scheduling using Bayesian statistics. (JavaScript, Java, Dart, and other ports available!)

    It seems from the description that FSRS still puts an exact review date on each card? This feature was pretty much the reason why I stopped using Anki. I'm not in college and not doing exams, I just want to practice when I feel like it, maybe with large breaks between sessions, and not feel like there's a backlog building up.

    I think Anki is a great app, I just wish there was an algorithm that would just randomly sample cards (with probability proportional to how urgently you need to review it) rather than put a review date on them. Something like https://github.com/fasiha/ebisu but available as an Anki plugin (if that supports custom algorithms on mobile yet?) or a similar app with an open format for cards.

  11. fsrs-vs-sm17

    A simple comparison between FSRS and SM-17

    Yeah, here is the comparison between FSRS and SM-17: https://github.com/open-spaced-repetition/fsrs-vs-sm17

  12. youtube2anki

NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.

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