Skip to content
@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.

Pinned Loading

  1. awesome-fsrs awesome-fsrs Public

    A curated list of awesome FSRS implementations, papers and resources

    377 24

  2. fsrs4anki fsrs4anki Public

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

    Jupyter Notebook 3.7k 153

  3. srs-benchmark srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    Jupyter Notebook 172 19

  4. ts-fsrs ts-fsrs Public

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

    TypeScript 515 52

  5. fsrs-rs fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    Rust 302 29

  6. fsrs4anki-helper fsrs4anki-helper Public

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

    Python 284 28

Repositories

Showing 10 of 85 repositories
  • srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    open-spaced-repetition/srs-benchmark’s past year of commit activity
    Jupyter Notebook 172 19 7 3 Updated Nov 30, 2025
  • fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    open-spaced-repetition/fsrs-rs’s past year of commit activity
    Rust 302 BSD-3-Clause 29 0 2 Updated Nov 28, 2025
  • 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 40 5 0 0 Updated Nov 27, 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 515 MIT 52 2 (1 issue needs help) 1 Updated Nov 25, 2025
  • lisp-fsrs Public

    Common/Emacs Lisp implementation for FSRS

    open-spaced-repetition/lisp-fsrs’s past year of commit activity
    Common Lisp 30 MIT 2 0 0 Updated Nov 19, 2025
  • anki-deck-specific-first-step Public

    Control your first learning steps!

    open-spaced-repetition/anki-deck-specific-first-step’s past year of commit activity
    JavaScript 0 0 0 0 Updated Nov 18, 2025
  • rs-fsrs-nodejs Public

    Nodejs binding for rs-fsrs.

    open-spaced-repetition/rs-fsrs-nodejs’s past year of commit activity
    Rust 3 MIT 0 1 1 Updated Nov 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 284 MIT 28 11 (6 issues need help) 0 Updated Nov 17, 2025
  • fsrs-optimizer Public

    FSRS Optimizer Package

    open-spaced-repetition/fsrs-optimizer’s past year of commit activity
    Python 93 BSD-3-Clause 15 0 3 Updated Nov 16, 2025
  • fsrs4anki Public

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

    open-spaced-repetition/fsrs4anki’s past year of commit activity
    Jupyter Notebook 3,696 MIT 153 9 0 Updated Nov 11, 2025