Tags: official-stockfish/Stockfish
Tags
Update NNUE architecture to SFNNv13 and net nn-5227780996d3.nnue Since the introduction of Threat Inputs in SFNNv10 and its refinements, the accumulator/L1 size has significantly decreased. This has made it more computationally favorable to double the L2 size from 16 to 32. Failed STC: LLR: -2.98 (-2.94,2.94) <0.00,2.00> Total: 189184 W: 49649 L: 49635 D: 89900 Ptnml(0-2): 881, 22479, 47812, 22585, 835 https://tests.stockfishchess.org/tests/view/69928ef7bfe62dc95a624d5c Passed LTC: LLR: 2.94 (-2.94,2.94) <0.50,2.50> Total: 37902 W: 9833 L: 9509 D: 18560 Ptnml(0-2): 35, 4074, 10408, 4400, 34 https://tests.stockfishchess.org/tests/view/69937936ff782f8eeef611e3 Passed VLTC SMP: LLR: 2.94 (-2.94,2.94) <0.50,2.50> Total: 20576 W: 5455 L: 5191 D: 9930 Ptnml(0-2): 6, 1837, 6338, 2101, 6 https://tests.stockfishchess.org/tests/view/6994df0586e4a32314116399 closes #6619 bench: 2396996
Stockfish 18 Official release version of Stockfish 18 Bench: 2050811 --- Stockfish 18 Today, we have the pleasure of announcing Stockfish 18, a new major release. As always, you can freely download it at [stockfishchess.org/download][1] and use it as a drop-in replacement in the [GUI of your choice][2] to benefit from stronger play and more accurate analysis. Whether you can spare hours or days of CPU time, your help matters for the ongoing development of Stockfish. Find out how you can help at [stockfishchess.org/get-involved][3]. Join our [Discord server][4] to get in touch with the community of developers and users of the project! Quality of chess play In tests against Stockfish 17, this new release brings an Elo gain of up to [46 points][5], and wins [four times as many game pairs][6] as it loses. Quality improved throughout, including in [Fischer Random Chess][7]. Stockfish is stronger than any human, even when running on older or low-end hardware. On the highest-end hardware, where Stockfish can search over [500 million positions per second][8], it continues to [dominate chess engine tournaments][9]. Update highlights Next-Generation Evaluation This release introduces the SFNNv10 network architecture. The network’s input layer has been augmented with 'Threat Inputs' features as part of a massive community effort. These features allow the engine to 'see' which pieces are threatened more naturally, resulting in more accurate evaluations. Hardware and Performance Optimizations A key highlight is the new 'Shared Memory' implementation, which allows different Stockfish processes to share the same memory space for neural network weights. This makes it the most efficient version for cloud analysis and high-concurrency testing. Significant efforts have also been made to utilize hardware more effectively by adapting the code to make use of modern CPU instructions and refining how threads interact during a search. Search Improvements Stockfish 18 features a heavily refined search, utilizing 'Correction History' to dynamically adjust evaluations based on patterns found during the search itself. These and other refinements allow the engine to detect stalemates and evaluate fortresses significantly better than previous versions. A particularly rare issue, involving threefold repetition detection, en passant, and pins, was also fixed. Refactored Training Workflow The training of Stockfish's neural networks has transitioned to an automated and reproducible model. This new framework allows the project to employ standardized recipes to chain complex training stages together. This transition facilitates the training of networks using over 100 billion positions of [Lc0 evaluation data][10]. Thank you In this release in particular, we are deeply grateful to the contributors who shared their research and ideas to help develop the new threat-input network architecture. The Stockfish project builds on a thriving community of enthusiasts (thanks to 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 [14.6k stars][11] that light up our GitHub project. Thank you for your support and encouragement – your recognition means a lot to us. 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://stockfishchess.org/get-involved/ [4]: https://discord.gg/GWDRS3kU6R [5]: https://tests.stockfishchess.org/tests/view/696a9e15cec152c6220c1d19 [6]: https://tests.stockfishchess.org/tests/view/696a9e4dcec152c6220c1d1b [7]: https://tests.stockfishchess.org/tests/view/696a9e83cec152c6220c1d1d [8]: https://openbenchmarking.org/test/pts/stockfish [9]: https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results [10]: https://lczero.org/blog/2021/06/the-importance-of-open-data/ [11]: https://github.com/official-stockfish/Stockfish/stargazers [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
Stockfish 18 Official release version of Stockfish 18 Bench: 2050811 --- Stockfish 18 Today, we have the pleasure of announcing Stockfish 18, a new major release. As always, you can freely download it at [stockfishchess.org/download][1] and use it as a drop-in replacement in the [GUI of your choice][2] to benefit from stronger play and more accurate analysis. Whether you can spare hours or days of CPU time, your help matters for the ongoing development of Stockfish. Find out how you can help at [stockfishchess.org/get-involved][3]. Join our [Discord server][4] to get in touch with the community of developers and users of the project! Quality of chess play In tests against Stockfish 17, this new release brings an Elo gain of up to [46 points][5], and wins [four times as many game pairs][6] as it loses. Quality improved throughout, including in [Fischer Random Chess][7]. Stockfish is stronger than any human, even when running on older or low-end hardware. On the highest-end hardware, where Stockfish can search over [500 million positions per second][8], it continues to [dominate chess engine tournaments][9]. Update highlights Next-Generation Evaluation This release introduces the SFNNv10 network architecture. The network’s input layer has been augmented with 'Threat Inputs' features as part of a massive community effort. These features allow the engine to 'see' which pieces are threatened more naturally, resulting in more accurate evaluations. Hardware and Performance Optimizations A key highlight is the new 'Shared Memory' implementation, which allows different Stockfish processes to share the same memory space for neural network weights. This makes it the most efficient version for cloud analysis and high-concurrency testing. Significant efforts have also been made to utilize hardware more effectively by adapting the code to make use of modern CPU instructions and refining how threads interact during a search. Search Improvements Stockfish 18 features a heavily refined search, utilizing 'Correction History' to dynamically adjust evaluations based on patterns found during the search itself. These and other refinements allow the engine to detect stalemates and evaluate fortresses significantly better than previous versions. A particularly rare issue, involving threefold repetition detection, en passant, and pins, was also fixed. Refactored Training Workflow The training of Stockfish's neural networks has transitioned to an automated and reproducible model. This new framework allows the project to employ standardized recipes to chain complex training stages together. This transition facilitates the training of networks using over 100 billion positions of [Lc0 evaluation data][10]. Thank you In this release in particular, we are deeply grateful to the contributors who shared their research and ideas to help develop the new threat-input network architecture. The Stockfish project builds on a thriving community of enthusiasts (thanks to 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 [14.6k stars][11] that light up our GitHub project. Thank you for your support and encouragement – your recognition means a lot to us. 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://stockfishchess.org/get-involved/ [4]: https://discord.gg/GWDRS3kU6R [5]: https://tests.stockfishchess.org/tests/view/696a9e15cec152c6220c1d19 [6]: https://tests.stockfishchess.org/tests/view/696a9e4dcec152c6220c1d1b [7]: https://tests.stockfishchess.org/tests/view/696a9e83cec152c6220c1d1d [8]: https://openbenchmarking.org/test/pts/stockfish [9]: https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results [10]: https://lczero.org/blog/2021/06/the-importance-of-open-data/ [11]: https://github.com/official-stockfish/Stockfish/stargazers [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
Stockfish 17.1 Official release version of Stockfish 17.1 Bench: 2030154 --- Stockfish 17.1 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! Quality of chess play 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. Update highlights New speedtest command 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! Improved hardware support 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. Bug fixes for tablebase support 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. Shoutouts Download page redesign 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. Fishtest framework 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. Thank you 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]: 652a887 [7]: 6c7c5c7 [8]: 0f9ae0d [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
Stockfish 17.1 Official release version of Stockfish 17.1 Bench: 2030154 --- Stockfish 17.1 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! Quality of chess play 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. Update highlights New speedtest command 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! Improved hardware support 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. Bug fixes for tablebase support 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. Shoutouts Download page redesign 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. Fishtest framework 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. Thank you 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]: 652a887 [7]: 6c7c5c7 [8]: 0f9ae0d [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
Stockfish 17 Official release version of Stockfish 17 Bench: 1484730 --- Stockfish 17 Today we have the pleasure to announce a new major release of Stockfish. As always, you can freely download it at https://stockfishchess.org/download and use it in the GUI of your choice. Don’t forget to join our Discord server[1] to get in touch with the community of developers and users of the project! *Quality of chess play* In tests against Stockfish 16, this release brings an Elo gain of up to 46 points[2] and wins up to 4.5 times more game pairs[3] than it loses. In practice, high-quality moves are now found in less time, with a user upgrading from Stockfish 14 being able to analyze games at least 6 times[4] faster with Stockfish 17 while maintaining roughly the same quality. During this development period, Stockfish won its 9th consecutive first place in the main league of the Top Chess Engine Championship (TCEC)[5], and the 24th consecutive first place in the main events (bullet, blitz, and rapid) of the Computer Chess Championship (CCC)[6]. *Update highlights* *Improved engine lines* This release introduces principal variations (PVs) that are more informative for mate and decisive table base (TB) scores. In both cases, the PV will contain all moves up to checkmate. For mate scores, the PV shown is the best variation known to the engine at that point, while for table base wins, it follows, based on the TB, a sequence of moves that preserves the game outcome to checkmate. *NUMA performance optimization* For high-end computers with multiple CPUs (typically a dual-socket architecture with 100+ cores), this release automatically improves performance with a `NumaPolicy` setting that optimizes non-uniform memory access (NUMA). Although typical consumer hardware will not benefit, speedups of up to 2.8x[7] have been measured. *Shoutouts* *ChessDB* During the past 1.5 years, hundreds of cores have been continuously running Stockfish to grow a database of analyzed positions. This chess cloud database[8] now contains well over 45 billion positions, providing excellent coverage of all openings and commonly played lines. This database is already integrated into GUIs such as En Croissant[9] and Nibbler[10], which access it through the public API. *Leela Chess Zero* Generally considered to be the strongest GPU engine, it continues to provide open data which is essential for training our NNUE networks. They released version 0.31.1[11] of their engine a few weeks ago, check it out! *Website redesign* Our website has undergone a redesign in recent months, most notably in our home page[12], now featuring a darker color scheme and a more modern aesthetic, while still maintaining its core identity. We hope you'll like it as much as we do! *Thank you* 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 11k stars[13] 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[14] to contribute compute resources needed for development. Programmers can contribute to the project either directly to Stockfish[15] (C++), to Fishtest[16] (HTML, CSS, JavaScript, and Python), to our trainer nnue-pytorch[17] (C++ and Python), or to our website[18] (HTML, CSS/SCSS, and JavaScript). The Stockfish team [1] https://discord.gg/GWDRS3kU6R [2] https://tests.stockfishchess.org/tests/view/66d738ba9de3e7f9b33d159a [3] https://tests.stockfishchess.org/tests/view/66d738f39de3e7f9b33d15a0 [4] https://github.com/official-stockfish/Stockfish/wiki/Useful-data#equivalent-time-odds-and-normalized-game-pair-elo [5] https://en.wikipedia.org/wiki/Stockfish_(chess)#Top_Chess_Engine_Championship [6] https://en.wikipedia.org/wiki/Stockfish_(chess)#Chess.com_Computer_Chess_Championship [7] #5285 [8] https://chessdb.cn/queryc_en/ [9] https://encroissant.org/ [10] https://github.com/rooklift/nibbler [11] https://github.com/LeelaChessZero/lc0/releases/tag/v0.31.1 [12] https://stockfishchess.org/ [13] https://github.com/official-stockfish/Stockfish/stargazers [14] https://github.com/official-stockfish/fishtest/wiki/Running-the-worker [15] https://github.com/official-stockfish/Stockfish [16] https://github.com/official-stockfish/fishtest [17] https://github.com/official-stockfish/nnue-pytorch [18] https://github.com/official-stockfish/stockfish-web
Stockfish 16.1 Official release version of Stockfish 16.1 Bench: 1303971 --- Stockfish 16.1 Today, we have the pleasure to announce Stockfish 16.1. As always, you can freely download it at https://stockfishchess.org/download and use it in the GUI of your choice[1]. Don't forget to join our Discord server[2] to get in touch with the community of developers and users of the project! *Quality of chess play* In our testing against its predecessor, Stockfish 16.1 shows a notable improvement in performance, with an Elo gain of up to 27 points and winning over 2 times more game pairs[3] than it loses. *Update highlights* *Improved evaluation* - Updated neural network architecture: The neural network architecture has undergone two updates and is currently in its 8th version[4]. - Removal of handcrafted evaluation (HCE): This release marks the removal of the traditional handcrafted evaluation and the transition to a fully neural network-based approach[5]. - Dual NNUE: For the first time, Stockfish includes a secondary neural network[6], used to quickly evaluate positions that are easily decided. *UCI Options removed* `Use NNUE` and `UCI_AnalyseMode`[7] have been removed as they no longer had any effect. `SlowMover`[8] has also been removed in favor of `Move Overhead`. *More binaries* We now offer 13 new binaries. These new binaries include `avx512`, `vnni256`, `vnni512`, `m1-apple-silicon`, and `armv8-dotprod`, which take advantage of specific CPU instructions for improved performance. For most users, using `sse41-popcnt` (formerly `modern`), `avx2`, or `bmi2` should be enough, but if your CPU supports these new instructions, feel free to try them! *Development changes* - Updated testing book: This new book[9], now derived exclusively from the open Lichess database[10], is 10 times larger than its predecessor, and has been used to test potential improvements to Stockfish over the past few months. - Consolidation of repositories: Aiming to simplify access to our resources, we have moved most Stockfish-related repositories into the official Stockfish organization[11] on GitHub. - Growing maintainer team: We welcome Disservin[12] to the team of maintainers of the project! This extra pair of hands will ensure the lasting success of Stockfish. *Thank you* 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 10k stars[13] 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[14], and programmers to contribute to the project either directly to Stockfish[15] (C++), to Fishtest[16] (HTML, CSS, JavaScript, and Python), to our trainer nnue-pytorch[17] (C++ and Python), or to our website[18] (HTML, CSS/SCSS, and JavaScript). The Stockfish team [1] https://github.com/official-stockfish/Stockfish/wiki/Download-and-usage#download-a-chess-gui [2] https://discord.gg/GWDRS3kU6R [3] https://tests.stockfishchess.org/tests/view/65d666051d8e83c78bfddbd8 [4] https://github.com/official-stockfish/nnue-pytorch/blob/master/docs/nnue.md#sfnnv8-architecture [5] af110e0 [6] 584d9ef [7] c53d2ec [8] 536d692 [9] official-stockfish/books@426eca4 [10] https://database.lichess.org/ [11] https://github.com/official-stockfish/ [12] https://github.com/Disservin [13] https://github.com/official-stockfish/Stockfish/stargazers [14] https://github.com/official-stockfish/fishtest/wiki/Running-the-worker [15] https://github.com/official-stockfish/Stockfish [16] https://github.com/official-stockfish/fishtest [17] https://github.com/official-stockfish/nnue-pytorch [18] https://github.com/official-stockfish/stockfish-web
Stockfish 16 Official release version of Stockfish 16 Bench: 2593605 --- Stockfish 16 A new major release of Stockfish is now available at https://stockfishchess.org/download/ *Quality of chess play* Stockfish continues to demonstrate its ability to discover superior moves with remarkable speed. In self-play against Stockfish 15, this new release gains up to 50 Elo[1] and wins up to 12 times more game pairs[2] than it loses. In major chess engine tournaments, Stockfish reliably tops the rankings[3] winning the TCEC season 24 Superfinal, Swiss, Fischer Random, and Double Random Chess tournaments and the CCC 19 Bullet, 20 Blitz, and 20 Rapid competitions. Leela Chess Zero[4] was the challenger in most finals, putting top-engine chess now firmly in the hands of teams embracing free and open-source software. *Progress made* This updated version of Stockfish introduces several enhancements, including an upgraded neural net architecture (SFNNv6)[5], improved implementation, and refined parameterization. The ongoing utilization of Leela’s data combined with a novel inference approach exploiting sparsity[6], and network compression[7] ensure a speedy evaluation and modest binary sizes while allowing for more weights and higher accuracy. The search has undergone more optimization, leading to improved performance, particularly in longer analyses[8]. Additionally, the Fishtest framework has been improved and is now able to run the tests needed to validate new ideas with 10000s of CPU cores. *Usability improvements* Stockfish now comes with documentation, found in the wiki folder when downloading it or on GitHub[9]. Additionally, Stockfish now includes a clear and consistent forced tablebase win score, displaying a value of 200 minus the number of plies required to reach a tablebase win[10]. Furthermore, the UCI_Elo option, to reduce its strength, has been calibrated[11]. It is worth noting that the evaluation system remains consistent with Stockfish 15.1[12], maintaining the choice that 100cp means a 50% chance of winning the game against an equal opponent[13]. Finally, binaries of our latest development version are now provided continuously as pre-releases on GitHub making it easier for enthusiasts to download the latest and strongest version of the program[14], we thank Roman Korba for having provided a similar service for a long time. *Thank you* The success of the Stockfish project relies on the vibrant community of passionate enthusiasts (we appreciate each and every one of you!) who generously contribute their knowledge, time, and resources. Together, this dedicated community works towards the common goal of developing a powerful, freely accessible, and open-source chess engine. We invite all chess enthusiasts to join the Fishtest testing framework and contribute to the project[15]. The Stockfish team [1] https://tests.stockfishchess.org/tests/view/649409f0dc7002ce609c99cc [2] https://tests.stockfishchess.org/tests/view/649409d7dc7002ce609c99c6 [3] https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results [4] https://lczero.org/ [5] c1fff71 [6] 38e6166 [7] a46087e [8] 472e726 [9] https://github.com/official-stockfish/Stockfish/wiki/ [10] def2966 [11] a08b8d4 [12] 52e84e4 [13] https://github.com/official-stockfish/Stockfish/wiki/Stockfish-FAQ#interpretation-of-the-stockfish-evaluation [14] https://github.com/official-stockfish/Stockfish/releases?q=prerelease%3Atrue [15] https://stockfishchess.org/get-involved/
Stockfish 16 Official release version of Stockfish 16 Bench: 2593605 --- Stockfish 16 A new major release of Stockfish is now available at https://stockfishchess.org/download/ *Quality of chess play* Stockfish continues to demonstrate its ability to discover superior moves with remarkable speed. In self-play against Stockfish 15, this new release gains up to 50 Elo[1] and wins up to 12 times more game pairs[2] than it loses. In major chess engine tournaments, Stockfish reliably tops the rankings[3] winning the TCEC season 24 Superfinal, Swiss, Fischer Random, and Double Random Chess tournaments and the CCC 19 Bullet, 20 Blitz, and 20 Rapid competitions. Leela Chess Zero[4] was the challenger in most finals, putting top-engine chess now firmly in the hands of teams embracing free and open-source software. *Progress made* This updated version of Stockfish introduces several enhancements, including an upgraded neural net architecture (SFNNv6)[5], improved implementation, and refined parameterization. The ongoing utilization of Leela’s data combined with a novel inference approach exploiting sparsity[6], and network compression[7] ensure a speedy evaluation and modest binary sizes while allowing for more weights and higher accuracy. The search has undergone more optimization, leading to improved performance, particularly in longer analyses[8]. Additionally, the Fishtest framework has been improved and is now able to run the tests needed to validate new ideas with 10000s of CPU cores. *Usability improvements* Stockfish now comes with documentation, found in the wiki folder when downloading it or on GitHub[9]. Additionally, Stockfish now includes a clear and consistent forced tablebase win score, displaying a value of 200 minus the number of plies required to reach a tablebase win[10]. Furthermore, the UCI_Elo option, to reduce its strength, has been calibrated[11]. It is worth noting that the evaluation system remains consistent with Stockfish 15.1[12], maintaining the choice that 100cp means a 50% chance of winning the game against an equal opponent[13]. Finally, binaries of our latest development version are now provided continuously as pre-releases on GitHub making it easier for enthusiasts to download the latest and strongest version of the program[14], we thank Roman Korba for having provided a similar service for a long time. *Thank you* The success of the Stockfish project relies on the vibrant community of passionate enthusiasts (we appreciate each and every one of you!) who generously contribute their knowledge, time, and resources. Together, this dedicated community works towards the common goal of developing a powerful, freely accessible, and open-source chess engine. We invite all chess enthusiasts to join the Fishtest testing framework and contribute to the project[15]. The Stockfish team [1] https://tests.stockfishchess.org/tests/view/649409f0dc7002ce609c99cc [2] https://tests.stockfishchess.org/tests/view/649409d7dc7002ce609c99c6 [3] https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results [4] https://lczero.org/ [5] c1fff71 [6] 38e6166 [7] a46087e [8] 472e726 [9] https://github.com/official-stockfish/Stockfish/wiki/ [10] def2966 [11] a08b8d4 [12] 52e84e4 [13] https://github.com/official-stockfish/Stockfish/wiki/Stockfish-FAQ#interpretation-of-the-stockfish-evaluation [14] https://github.com/official-stockfish/Stockfish/releases?q=prerelease%3Atrue [15] https://stockfishchess.org/get-involved/
Stockfish 15.1 Official release version of Stockfish 15.1 Bench: 3467381 --- Today, we have the pleasure to announce Stockfish 15.1. As usual, downloads will be freely available at stockfishchess.org/download *Elo gain and competition results* With this release, version 5 of the NNUE neural net architecture has been introduced, and the training data has been extended to include Fischer random chess (FRC) positions. As a result, Elo gains are largest for FRC, reaching up to 50 Elo for doubly randomized FRC[1] (DFRC). More importantly, also for standard chess this release progressed and will win two times more game pairs than it loses[2] against Stockfish 15. Stockfish continues to win in a dominating way[3] all chess engine tournaments, including the TCEC Superfinal, Cup, FRC, DFRC, and Swiss as well as the CCC Bullet, Blitz, and Rapid events. *New evaluation* This release also introduces a new convention for the evaluation that is reported by search. An evaluation of +1 is now no longer tied to the value of one pawn, but to the likelihood of winning the game. With a +1 evaluation, Stockfish has now a 50% chance of winning the game against an equally strong opponent. This convention scales down evaluations a bit compared to Stockfish 15 and allows for consistent evaluations in the future. *ChessBase settlement* In this release period, the Stockfish team has successfully enforced its GPL license against ChessBase. This has been an intense process that included filing a lawsuit[4], a court hearing[5], and finally negotiating a settlement[6] that established that ChessBase infringed on the license by not distributing the Stockfish derivatives Fat Fritz 2 and Houdini 6 as free software, and that ensures ChessBase will respect the Free Software principles in the future. This settlement has been covered by major chess sites (see e.g. lichess.org[7] and chess.com[8]), and we are proud that it has been hailed as a ‘historic violation settlement[9]’ by the Software Freedom Conservancy. *Thank you* The Stockfish project builds on a thriving community of enthusiasts (thanks everybody!) that contribute their expertise, time, and resources to build a free and open-source chess engine that is robust, widely available, and very strong. We invite our chess fans to join the fishtest testing framework and programmers to contribute to the project[10]. The Stockfish team [1] https://tests.stockfishchess.org/tests/view/638a6170d2b9c924c4c62cb4 [2] https://tests.stockfishchess.org/tests/view/638a4dd7d2b9c924c4c6297b [3] https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results [4] https://stockfishchess.org/blog/2021/our-lawsuit-against-chessbase/ [5] https://stockfishchess.org/blog/2022/public-court-hearing-soon/ [6] https://stockfishchess.org/blog/2022/chessbase-stockfish-agreement/ [7] https://lichess.org/blog/Y3u1mRAAACIApBVn/settlement-reached-in-stockfish-v-chessbase [8] https://www.chess.com/news/view/chessbase-stockfish-reach-settlement [9] https://sfconservancy.org/news/2022/nov/28/sfc-named-trusted-party-in-gpl-case/ [10] https://stockfishchess.org/get-involved/
PreviousNext