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@open-spaced-repetition

Open Spaced Repetition

We are developing open-source spaced repetition algorithms for any spaced repetition software/system.

About

Open Spaced Repetition (OSR) is an open-source community dedicated to the advancement of spaced repetition algorithms. We are the creators of the Free Spaced Repetition Scheduler (FSRS), which is backed by academic literatures and experiments. FSRS has been implemented in various programming languages, including Javascript, Golang, Rust, Python, and so on.

Mission

Our mission is to develop efficient, effective, and accessible spaced repetition algorithms that can be readily integrated into any educational software or system.

Features

Acknowledgements

A special thanks to 墨墨背单词 (MaiMemo Inc.) for their support of FSRS development by allowing its research engineer, Jarrett Ye, to dedicate part of his working hours to this open-source project. This greatly helps in the continuous improvement and maintenance of FSRS for the benefit of the entire community.

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  1. awesome-fsrs awesome-fsrs Public

    A curated list of awesome FSRS implementations, papers and resources

    358 23

  2. fsrs4anki fsrs4anki Public

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

    Jupyter Notebook 3.6k 152

  3. srs-benchmark srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    Jupyter Notebook 164 19

  4. ts-fsrs ts-fsrs Public

    ts-fsrs is a versatile package written in TypeScript that supports ES modules, CommonJS, and UMD.

    TypeScript 486 48

  5. fsrs-rs fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    Rust 293 28

  6. fsrs4anki-helper fsrs4anki-helper Public

    An Anki add-on that supports Postpone & Advance & Load Balance & Easy Days & Disperse Siblings & Flatten

    Python 281 28

Repositories

Showing 10 of 84 repositories
  • fsrs-vs-sm17 Public

    A simple comparison between FSRS and SM-17

    open-spaced-repetition/fsrs-vs-sm17’s past year of commit activity
    Jupyter Notebook 37 5 0 0 Updated Oct 21, 2025
  • fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    open-spaced-repetition/fsrs-rs’s past year of commit activity
    Rust 293 BSD-3-Clause 28 0 1 Updated Oct 21, 2025
  • ts-fsrs Public

    ts-fsrs is a versatile package written in TypeScript that supports ES modules, CommonJS, and UMD.

    open-spaced-repetition/ts-fsrs’s past year of commit activity
    TypeScript 486 MIT 48 2 2 Updated Oct 20, 2025
  • fsrs-rs-python Public

    Python bindings for fsrs-rs, use burn-rs, instead of pytorch. 2GB -> 6MB, save your disk!

    open-spaced-repetition/fsrs-rs-python’s past year of commit activity
    Rust 28 2 2 2 Updated Oct 20, 2025
  • srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    open-spaced-repetition/srs-benchmark’s past year of commit activity
    Jupyter Notebook 164 19 7 3 Updated Oct 18, 2025
  • fsrs4anki-helper Public

    An Anki add-on that supports Postpone & Advance & Load Balance & Easy Days & Disperse Siblings & Flatten

    open-spaced-repetition/fsrs4anki-helper’s past year of commit activity
    Python 281 MIT 28 11 (6 issues need help) 0 Updated Oct 17, 2025
  • py-fsrs Public

    Python Package for FSRS Spaced Repetition

    open-spaced-repetition/py-fsrs’s past year of commit activity
    Python 349 MIT 46 0 0 Updated Oct 16, 2025
  • open-spaced-repetition/Anki-Search-Stats-Extended’s past year of commit activity
    Svelte 0 GPL-3.0 15 0 0 Updated Oct 10, 2025
  • fsrs-browser Public

    FSRS for the browser, including Optimizer and Scheduler

    open-spaced-repetition/fsrs-browser’s past year of commit activity
    TypeScript 44 BSD-3-Clause 3 0 0 Updated Oct 2, 2025
  • fsrs-optimizer Public

    FSRS Optimizer Package

    open-spaced-repetition/fsrs-optimizer’s past year of commit activity
    Python 90 BSD-3-Clause 14 0 2 Updated Oct 1, 2025