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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

    405 24

  2. fsrs4anki fsrs4anki Public

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

    Jupyter Notebook 3.7k 156

  3. srs-benchmark srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    Jupyter Notebook 181 19

  4. ts-fsrs ts-fsrs Public

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

    TypeScript 540 52

  5. fsrs-rs fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    Rust 316 29

  6. fsrs4anki-helper fsrs4anki-helper Public

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

    Python 289 28

Repositories

Showing 10 of 85 repositories
  • 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 540 MIT 52 0 5 Updated Jan 5, 2026
  • srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    open-spaced-repetition/srs-benchmark’s past year of commit activity
    Jupyter Notebook 181 19 7 4 Updated Jan 5, 2026
  • rs-fsrs Public

    Rust-based Scheduler for FSRS

    open-spaced-repetition/rs-fsrs’s past year of commit activity
    Rust 46 MIT 9 1 0 Updated Jan 4, 2026
  • swift-fsrs Public

    Swift Package for FSRS

    open-spaced-repetition/swift-fsrs’s past year of commit activity
    Swift 75 MIT 25 3 0 Updated Jan 4, 2026
  • 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 41 5 0 0 Updated Jan 4, 2026
  • rb-fsrs Public

    A ruby implementation of the Open Spaced Repetition's Free Spaced Repetition Scheduler

    open-spaced-repetition/rb-fsrs’s past year of commit activity
    Ruby 18 MIT 13 3 3 Updated Dec 30, 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 30 2 2 2 Updated Dec 30, 2025
  • fsrs-rs-c Public

    c binding, also dynamic library

    open-spaced-repetition/fsrs-rs-c’s past year of commit activity
    C 6 MIT 1 0 0 Updated Dec 29, 2025
  • anki-manual-zh-CN Public

    Anki 用户手册(中文翻译)

    open-spaced-repetition/anki-manual-zh-CN’s past year of commit activity
    CSS 50 8 0 0 Updated Dec 16, 2025
  • fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    open-spaced-repetition/fsrs-rs’s past year of commit activity
    Rust 316 BSD-3-Clause 29 1 2 Updated Dec 15, 2025