Today, we have the pleasure to announce Stockfish 17.1. As always, you can **freely** download it at [stockfishchess.org/download][1] and use it in the [GUI of your choice][2].

Join our [Discord server][3] to get in touch with the community of developers and users of the project!

In our testing against its predecessor, Stockfish 17.1 shows a consistent improvement in performance, with an [Elo gain of up to 20 points][4] and winning close to 2 times more game pairs than it loses.

The new `speedtest` command benchmarks your computer's performance (measured in nodes per second) using a realistic and stable test. To run it, you'll need [command line access][5]—give it a try and share your results with the community!

Stockfish is [no longer limited to 1024 threads][6] and will allow users to specify whatever their system is capable of. Additionally, hardware such as ppc64 and Loongson is now better supported at build time.

Our previous release introduced improved engine lines (principal variations) ending in mate as soon as a mate score is announced. A side effect of this improvement was a [rare corner case][7] involving cursed tablebase wins, only relevant in correspondence chess when the 50-move rule does not apply, which has now been fixed. Relatedly, [time management][8] has also been improved to avoid potential time losses.

We've redesigned the [download page][1] to address unclear wording and simplify a previously cluttered experience. The page now features a modernized layout, streamlined navigation, and clearer guidance to help you select the right binary for your system.

Our testing framework has been improved in various ways, both on the worker side, including the adoption of [Fastchess][9] as a new game manager, and on the server side, such as streamlined configuration. The reliable availability of testing resources is key for the progress of the engine.

The Stockfish project builds on a thriving community of enthusiasts (thanks everybody!) who contribute their expertise, time, and resources to build a free and open-source chess engine that is robust, widely available, and very strong.

We would like to express our gratitude for the [12k stars][10] that light up our GitHub project! Thank you for your support and encouragement – your recognition means a lot to us.

We invite our chess fans to [join the Fishtest testing framework][11] to contribute compute resources needed for development. Programmers can contribute to the project either directly to [Stockfish][12] (C++), to [Fishtest][13] (HTML, CSS, JavaScript, and Python), to our trainer [nnue-pytorch][14] (C++ and Python), or to our [website][15] (HTML, CSS/SCSS, and JavaScript).

The Stockfish team

[1]: https://stockfishchess.org/download

[2]: https://official-stockfish.github.io/docs/stockfish-wiki/Download-and-usage.html#download-a-chess-gui

[3]: https://discord.gg/GWDRS3kU6R

[4]: https://tests.stockfishchess.org/tests/view/67e7d2fd6682f97da2178fbd

[5]: https://official-stockfish.github.io/docs/stockfish-wiki/UCI-&-Commands.html#speedtest

[6]: https://github.com/official-stockfish/Stockfish/commit/652a8874b523360a3b19c5003c8ba9894ac54d0f

[7]: https://github.com/official-stockfish/Stockfish/commit/6c7c5c7e471c16f14518229428e51a3e00c0f1dd

[8]: https://github.com/official-stockfish/Stockfish/commit/0f9ae0d11cd034288a49ef3892c580dfed025091

[9]: https://github.com/Disservin/fastchess

[10]: https://github.com/official-stockfish/Stockfish/stargazers

[11]: https://official-stockfish.github.io/docs/fishtest-wiki/Running-the-Worker.html

[12]: https://github.com/official-stockfish/Stockfish

[13]: https://github.com/official-stockfish/fishtest

[14]: https://github.com/official-stockfish/nnue-pytorch

[15]: https://github.com/official-stockfish/stockfish-web