Othello AI Egaroucid
This page is a machine translation of the Japanese version. Please refer to the Japanese version for the official content.
Egaroucid [ɪɡɑɻˈəʊsid] is an Othello app with one of the strongest othello solver AI.
Download Egaroucid 7.8.0
Lineup
Completely free software. Egaroucid and Egaroucid for Console use the same (strong) engine, but Egaroucid for Web uses a simple (weaker) engine.
| Name | Platforms |
|---|---|
| Egaroucid | Windows |
| Egaroucid for Console | Windows MacOS Linux |
| Egaroucid for Web | Any Web Browser |
Competitive Results
- Runner-up in Othello AI Tournament @Generic Game Server (2025/11/01)
- Othello AI Tournament Champion @Generic Game Server (2024/12/08)
- CodinGame Othello World Champion (2021/11/22, 2023/09/08, 2025/02/01)
Features
- Accurate and fast evaluation function
- Fast search
- Play against AI
- on Egaroucid's GUI
- on other GUI with Go Text Protocol (GTP) (Egaroucid for Console)
- GoGui
- Quarry
- Analyze a game
- See evaluation values
- Input and Output in several formats
- Create / Modify book automatically / manually
- Add Egaroucid's / Edax's book
- Show opening name
- Beautiful GUI powered by Siv3D
How to Install Egaroucid
Egaroucid
Please visit download page and download installer, then install Egaroucid.
Egaroucid for Console
Please read how to install Egaroucid for Console and download or build it.
Egaroucid for Web
You don't need to do anything special. Please just visit Egaroucid for Web page and play now.
Official Documents
There are some official documents of Egaroucid written in Japanese. Please translate it by yourself.
- How to Use Egaroucid: Explains how to use the software one by one
- Book Usage: Explains how to use Egaroucid's book
- Technology Explanation: Technical explanation for Othello AI programmers
Articles that introduce Egaroucid
- The university student who created the world's strongest "Othello AI" - The starting point of creation was "a single picture book": Detailed introduction by QuizKnock Web media
- Egaroucid: An Othello app review: Review of Egaroucid by World Othello Federation
Other Documents
Other materials related to Egaroucid. Mostly for reading. (Available in Japanese only)
- How I became World No. 1 in Othello AI and completely understood Othello AI: The story of how I reached No. 1 in a contest at the beginning of Othello AI development
- How I won the Othello AI World Championship: The story of how I won an Othello AI tournament with few restrictions. After 3 years, I have almost reached the "true world's strongest" Othello AI I wrote about in my previous post.
- Everyone, just build an Othello AI: Explains the benefits of building an Othello AI
- Othello AI Textbook: A magazine explaining Othello AI production from scratch. Completely free. Sample code is also available. These are somewhat old articles, so I hope to update them soon...
- How the World No. 1 Othello AI creator made the weakest Othello AI (Story): The story of creating the weakest Othello AI, Egaroucen (the weakest in the world according to my own research)
- How the World No. 1 Othello AI creator made the weakest Othello AI (Technical): Technical explanation of the weakest Othello AI, Egaroucen
- How I made my first app by turning the World No. 1 Othello AI into software with Siv3D: The story of releasing the Othello AI as a software that actually works on the screen
Materials about Othello is Solved
On October 30, 2023, a paper titled Othello is Solved was posted to arXiv. I am not the author of this paper, but since it is in my specialty, I read it and wrote a commentary on it. It is not directly related to Egaroucid, but my experience in developing Egaroucid was helpful in understanding the paper, so I will introduce it here. It is probably the most accurate and detailed explanation available in Japanese.
- Othello is Solved (Hiroki Takizawa): Original paper (English).
- Let's make it clear whether "Othello is Solved" or not: An article written as a special commentary in the journal of the Information Processing Society of Japan (IPSJ). I summarized the paper's commentary briefly.
- Commentary on the Othello is Solved Paper (Personal View): A long text of 17,000 characters, explaining the paper in detail.
Looking for your voice
Via this Google form, you can send me messages such as:
- I found a bug!
- I want to use Egaroucid in my language!
- I want some new functions!
- I have a good idea to improve!
- I want to participate in user tests!
I would like to hear your voice! Please contact me freely!
Welcome your contribution on Egaroucid
Egaroucid is an open source software under GPL-3.0 license. All source codes are available on GitHub here. I welcome your contributions such as pull requests!
When you want to use Egaroucid in your own software
You can use Egaroucid freely under GPL-3.0 license. If you worry about GPL-infection, please ask me.
If you use Egaroucid, I would be happy to receive a report (not mandatory).
Citation
We welcome the use of Egaroucid in papers and other publications.
When citing Egaroucid, please use the following format as a reference, or adjust it to fit the citation format of your publication.
Yamana, Takuto.: Egaroucid, https://www.egaroucid.nyanyan.dev/
Acknowledgements
I would like to thank these people for great contributions (in no particular order, titles omitted).
- UI Design
- Kaneko Eizo
- Technical Contribution / GitHub Contribution
- Toshihiko Okuhara
- Hayato Sasakura
- acepck
- Sotaro Ishii
- Folkert van Heusden
- HiraokaTakuya
- Ben Stokmans
- seigot
- Translation
- ZhangHengge (Simplified Chinese)
- YuYutw123 (Traditional Chinese (Taiwan))
- Technical Advice
- Jon Marc Hornstein
- Opening names Organize / Provision
- Kyrin
- Wanryu
- Uenon
- Matthias Berg
- Book Provision
- Gunnar Andersson
- User Test
- Ben Seeley
- Wanryu
- OGA NAO
- Satoshi Kurahashi
- Taiki Demoto
- Mathica
- Nettle
- okojoMK
- Takada Seigo
- madaranuko
- Nagano Yasushi
- trineutron
- Kuruton
Links
Third-Party Links
Below is a list of Egaroucid-related links provided by third parties. The author of Egaroucid assumes no responsibility for the content of these links.
- Distribution of books in Egaroucid format (Japanese): High-precision books that can be used directly with Egaroucid are being made available to the public.
Works by third parties using Egaroucid-related materials
These are works developed by third parties using Egaroucid or Egaroucid's training data, etc.
- Reversi Web: Othello AI that can be played on the website. The Egaroucid for Web engine is used as the top-level AI that you can play against by winning and advancing.
- Reversi Nexus: Othello AI that can be played on websites, desktops, and mobiles. It seems they referred to Egaroucid's training data and technical explanation.
Other Othello AIs
Recent great Othello AIs:
- Edax 4.6: Strong and famous. Egaroucid borrows many ideas from Edax.
- Edax 4.5: Edax 4.4 optimized for AVX. Strong and very fast. Egaroucid borrows some ideas from Edax 4.5.
- Master Reversi: Strong and very fast.
- FOREST: Uses alpha-beta pruning with neural-network-based evaluation function. The accuracy of its evaluation function is very good.
- dekunobou: An unique Othello AI which uses alpha-beta pruning with an evaluation function optimized by genetic algorithm. The developer is also famous for shogi AI.
- WZebra: Development stopped in around 2005. In old versions of Egaroucid, the default book was based on WZebra's book under a permission of its developer. Although the development has already stopped, I would like to introduce it with respect.
- Logistello: The first Othello AI to win against world champion Takeshi Murakami in 1997. The idea of this AI is used in Egaroucid even now. Although the development has already stopped, I would like to introduce it with respect.