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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 Public

    A curated list of awesome FSRS implementations, papers and resources

    274 15

  2. fsrs4anki Public

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

    Jupyter Notebook 3.5k 150

  3. fsrs4anki-helper Public

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

    Python 258 27

  4. fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    Rust 270 26

  5. ts-fsrs Public

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

    TypeScript 407 43

  6. srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    Jupyter Notebook 138 15

Repositories

Showing 10 of 79 repositories
  • java-fsrs Public

    Java library for FSRS Spaced Repetition

    Java 1 MIT 0 0 0 Updated Jul 15, 2025
  • fsrs-rs Public

    FSRS for Rust, including Optimizer and Scheduler

    Rust 270 BSD-3-Clause 26 0 1 Updated Jul 15, 2025
  • fsrs4anki-helper Public

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

    Python 258 MIT 27 11 (6 issues need help) 0 Updated Jul 14, 2025
  • fsrs-rs-php Public

    A PHP binding for the FSRS (Free Spaced Repetition Scheduler) Rust implementation.

    Rust 2 0 0 1 Updated Jul 14, 2025
  • srs-benchmark Public

    A benchmark for spaced repetition schedulers/algorithms

    Jupyter Notebook 138 15 9 2 Updated Jul 14, 2025
  • ts-fsrs Public

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

    TypeScript 407 MIT 43 0 1 Updated Jul 14, 2025
  • anki_fsrs_visualizer Public

    Anki FSRS Visualizer

    Vue 26 MIT 6 0 0 Updated Jul 13, 2025
  • lisp-fsrs Public

    Common/Emacs Lisp implementation for FSRS

    Common Lisp 26 MIT 1 0 0 Updated Jul 12, 2025
  • fsrs-optimizer Public

    FSRS Optimizer Package

    Python 86 BSD-3-Clause 14 0 3 Updated Jul 9, 2025
  • fsrs-rs-c Public

    c binding, also dynamic library

    C 1 MIT 0 0 0 Updated Jul 8, 2025