Changes

[[FILE:stockfish-logo.png|border|right|thumb|| Stockfish logo <ref>The Stockfish icon was designed by [http://iamkle.in/ Klein Maetschke], [https://stockfishchess.org/about/ About - Stockfish]</ref> ]] [[FILE:stockfish12-logo.png|border|right|thumb|link=https://stockfishchess.org/| Stockfish 12 logo <ref>[https://stockfishchess.org/ Stockfish - Open Source Chess Engine], The Stockfish 12 icon was designed by [http://iamkle.in/ Klein Maetschke], [https://stockfishchess.org/about/ About - Stockfish]</ref> ]]

an [[UCI]] compatible [[:Category:Open Source|open source]] chess engine developed by [[Tord Romstad]], [[Marco Costalba]], [[Joona Kiiski]] and [[Gary Linscott]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=58779 Stockfish 7] by [[Joona Kiiski]], [[CCC]], January 02, 2016</ref>, licensed under the [[Free Software Foundation#GPL|GPL v3.0]]. Marco forked the project from version 2.1 of Tord's engine [[Glaurung]], first announced by Marco in November 8, 2008 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=24675 Stockfish 1.0] by [[Marco Costalba]], [[CCC]], November 02, 2008</ref>, and in early 2009 Joona's [[Smaug]], a further Glaurung 2.2 derivative, was incorporated <ref>[http://www.talkchess.com/forum/viewtopic.php?t=26971&start=1 Re: Smaug: a new chess engine based on glaurung] by [[Marco Costalba]], [[CCC]], March 12, 2009</ref> . Starting out among the top twenty engines, Stockfish has quickly climbed in [[Playing Strength|strength]] to become the world strongest chess entity as of 2018 - at least concerning the [[AlphaZero]] hype <ref>[[David Silver]], [[Thomas Hubert]], [[Julian Schrittwieser]], [[Ioannis Antonoglou]], [[Matthew Lai]], [[Arthur Guez]], [[Marc Lanctot]], [[Laurent Sifre]], [[Dharshan Kumaran]], [[Thore Graepel]], [[Timothy Lillicrap]], [[Karen Simonyan]], [[Demis Hassabis]] ('''2017'''). ''Mastering Chess and Shogi by Self-Play with a General Reinforcement Learning Algorithm''. [https://arxiv.org/abs/1712.01815 arXiv:1712.01815]</ref>, public available chess entity. The name "Stockfish" reflects the ancestry of the engine. Tord is Norwegian and Marco Italian, and there is a long history of [https://en.wikipedia.org/wiki/Stockfish stockfish] trade from Norway to Italy (to Marco's home town of [https://en.wikipedia.org/wiki/Vicenza Vicenza], in fact). Stockfish also referred another famous "little fish", the then strongest chess engine [[Rybka]]. In 2011, Marco Costalba and Joona Kiiski stepped down as Stockfish maintainers <ref>[http://www.talkchess.com/forum/viewtopic.php?t=40610 Stockfish on github] by [[Marco Costalba]], [[CCC]], October 02, 2011</ref>. From that, the project is being developed and maintained by the [[:Category:Stockfish Contributor|Stockfish community]].  A synergy effect with the [[Shogi]] community led to the promising branch of [[Stockfish NNUE]], courtesy of [[Hisayori Noda|Nodchip]], who introduced [[NNUE]] to Stockfish in 2019 <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=2&t=74059 Stockfish NN release (NNUE)] by [[Henk Drost]], [[CCC]], May 31, 2020</ref>. On September 02, 2020, '''Stockfish 12''' was released with a huge jump in [[Playing Strength|playing strength]] due to NNUE and further [[Automated Tuning|tuning]] of the engine <ref>[https://stockfishchess.org/blog/2020/stockfish-12/ Stockfish 12], The Stockfish Team, [https://blog.stockfishchess.org/ Stockfish Blog], September 02, 2020</ref>. The release of '''Stockfish 13''' on February 19, 2021, has been triggered by the start of sales of the [[Fat Fritz#Fat Fritz 2|Fat Fritz 2]] engine by [[ChessBase]], based on a recent development version of Stockfish with minor modifications <ref>[https://stockfishchess.org/blog/2021/stockfish-13/ Stockfish 13], The Stockfish Team, February 19, 2021</ref>. '''Stockfish 14''', released on July 02, 2021, further improved due to efforts by [[Tomasz Sobczyk]] and [[Gary Linscott]] in designing a new [[Stockfish NNUE#HalfKA|NNUE architecture]] in conjunction with a [[GPU]] accelerated trainer written in [https://en.wikipedia.org/wiki/PyTorch PyTorch]. Further, the collaboration with the [[Leela Chess Zero]] team payed off, in providing billions of positions to train the new NNUE <ref>[https://stockfishchess.org/blog/2021/stockfish-14/ Stockfish 14], The Stockfish Team, July 02, 2021</ref>. '''Stockfish 16''', released June 30, 2023, removes the classical [[Evaluation|evaluation]] from the engine and focuses on [[NNUE]] neural networks.<ref>[https://github.com/official-stockfish/Stockfish/commit/af110e02ec96cdb46cf84c68252a1da15a902395 GitHub - Stockfish commit, Remove classical evaluation]</ref>

There is a wide range of opinions about strong open source chess engines affecting commercial and competitive interests, as well as monetary interests from computer chess users, who obtain a top engine for free. The scientific and social value of strong open -source programs is indisputable. The [https://en.wikipedia.org/wiki/Teamwork teamwork] effort to share ideas and knowledge to write one of the strongest programs, which everybody may follow and share to learn and play for free, is definitely a challenging and motivating task, gathering both admiration and enviousness. Obviously, professional programmers of commercial chess programs are not that enthusiastic about the development, and need to improve further and/or focus more on secondary features or other business concepts like on-line online play and/or [[GUI|user interface]] issues rather than on pure playing strength.

Also , many hobbyist chess programmers feel in the antagonism as well, not only caused by Stockfish with its highly respected authors, and before by [[Fruit]] and slightly [[Crafty]], but from [[Ippolit]] and all its successors by pseudonymous authors and disputed origin. The implications on commercial and competitive computer chess are not quite clear, but presumably , the decrease in the number of participants of over the board [[Tournaments and Matches|tournaments]] will progress and [[Clones:Category:Clone|clone]] suspicions may float like a [https://en.wikipedia.org/wiki/Damocles Sword of Damocles] over the scene, whether programmers took ideas too literally or not.

Since Stockfish is written in [[Cpp|C++]], it may be compiled and build built for various processors and operating systems . The main source code of Stockfish could be compiled directly into [[CLI|Command Line Interface]] program. Some programmers have added code to change it into a [[GUI|Graphical User Interface]] one which may be compulsory to run on some platforms such as iOS.==[[AndroidCLI|Command Line Interface]], ==* Stockfish for [[iOSAndroid]], [[Linux]], [[Mac OS|OS XmacOS]], and [[Windows]]was officially built by the developer team and published on both [https://stockfishchess.org/ Stockfish website] and [https://github. com/official-stockfish/Stockfish Stockfish GitHub]==Stockfish with built-in [[GUI|Graphical User Interface]]==We list only some programs that are popular and license compliance (released with source code):* Stockfish for [[MacintoshMac OS|macOS]] was also built and published on [[Mac App Store]] by [[Daylen Yang]], who is also responsible for the Stockfish website. * Stockfish for [[iOS]] was built by Tord Romstad <ref>[https://stockfishchess.org/about/ About - Stockfish]</ref>.

Since April 2017 the interactive '''Stockfish Evaluation Guide''' is available to explore Stockfish's [[Evaluation|evaluation]] with a [[JavaScript]] implementation running in a [https://en.wikipedia.org/wiki/Web_browser browser] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=64025&start=27 Re: How far away are we from deep learning Stockfish, Komodo] by [[Gary Linscott|Gary]], [[CCC]], May 21, 2017</ref> . One may enter a [[Forsyth-Edwards Notation|FEN]] string of a [[Chess Position|position]], to get the resulting [[Score|score]] of the main evaluation term considering the [[Game Phases|game phases]] within its [[Tapered Eval|tapered evaluation]], and may navigate through the tree of subterms and features with its particular characteristics for the given position <ref>[https://hxim.github.io/Stockfish-Evaluation-Guide/ Stockfish Evaluation Guide]</ref>, also supporting [[Stockfish NNUE]] nets <ref>[https://hxim.github.io/Stockfish-Evaluation-Guide/?p=nnue Stockfish Evaluation Guide - NNUE]</ref> .

Stockfish is top contender of the prestigious [[TCEC|Thoresen Top Chess Engines Competition (TCEC)]], reaching the superfinals since [[TCEC Season 4|season 4]], and clearly established its world number one status in winning recent TCECs, leaving its commercial rivals [[Komodo]] and [[Houdini]] behind.Since [[TCEC_Season_14#Superfinal|season 14]] in early 2019, Stockfish competes with the [[Deep Learning|deep learning]] [[Leela Chess Zero]] engines, whose [[Playing Strength|playing strength]] triggered a motivation boost in the developing community to further improve Stockfish.

On July 19, 2014, Stockfish 5 played a four game match versus [https://en.wikipedia.org/wiki/Daniel_Naroditsky Daniel Naroditsky] plus [[Rybka|Rybka 3]] (2008), 45 minutes plus 30-second increment. Stockfish won 3½ - ½ <ref>[http://www.chess.com/article/view/how-rybka-and-i-tried-to-beat-the-strongest-chess-computer-in-the-world Can a GM and Rybka beat Stockfish?] by GM [https://en.wikipedia.org/wiki/Daniel_Naroditsky Daniel Naroditsky], [https://en.wikipedia.org/wiki/Chess.com [Chess.com]], August 08, 2014</ref> <ref>[http://www.talkchess.com/forum/viewtopic.php?t=53228 GM and Rybka vs. Stockfish] by Robert Maddox, [[CCC]], August 09, 2014</ref> . A few weeks later the experiment continued with [https://en.wikipedia.org/wiki/Hikaru_Nakamura Hikaru Nakamura] in [https://en.wikipedia.org/wiki/Burlingame,_California Burlingame, California] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=53315 Nakamura vs Stockfish, public match 8/23] by Jesse L, [[CCC]], August 17, 2014</ref> . Supported two games by Rybka 3, Nakamura lost ½ - 1½, two games with pawn odds (Stockfish both Black without h- and b-pawn) ended ½ - 1½ in favour to Stockfish 5 as well. It played the latest development build compiled for [[Mac OS|OS X]] running on a 3 GHz 8-Core [[Macintosh|Mac Pro]] <ref>[http://www.chess.com/news/stockfish-outlasts-nakamura-3634 Stockfish Outlasts "Rybkamura"] by [http://www.chess.com/article/view/chesscom-player-profiles-fm-mikeklein FM Mike Klein], [https://en.wikipedia.org/wiki/Chess.com [Chess.com]], August 24, 2014</ref> .

: [[BMI2#PEXTBitboards|BMI2 - PEXT Bitboards]] (not recommend for [[AMD]] [https://en.wikipedia.org/wiki/Ryzen Ryzen] <ref>[https://www.reddit.com/r/Amd/comments/60i6er/ryzen_and_bmi2_strange_behavior_and_high_latencies/ Ryzen and BMI2: Strange behavior and high latencies] by DonnieTinyHands, [https://en.wikipedia.org/wiki/Reddit Reddit], March 20, 2017</ref>prior to [https://en.wikipedia.org/wiki/Zen_3 Zen 3])* [[Piece-Lists]] until Stockfish 12 <ref>[https://github.com/official-stockfish/Stockfish/blob/sf_12/src/position.h#L193 Stockfish/position.h at sf_12 · official-stockfish/Stockfish · GitHub]</ref> <ref>[https://github.com/official-stockfish/Stockfish/pull/3247 Remove piece lists by syzygy1 · Pull Request #3247 · official-stockfish/Stockfish · GitHub]</ref> <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=7&t=69364&start=12 Re: piece lists advantage with bit-boards?] by [[Ronald de Man]], [[CCC]], December 26, 2018</ref>

<ref>* [[NNUE]]** [[Stockfish NNUE#HalfKP|HalfKP]] (Stockfish 12)** [[Stockfish NNUE#HalfKA|HalfKAv2]] (Stockfish 14): ''See also '' [[Evaluation Philosophy]] and <ref>[http://www.talkchess.com/forum/viewtopic.php?topic_view=threads&p=135133&t=15504 The Art of Evaluation] by [[Tord Romstad]], [[CCC]], August 2, 2007</ref> <ref>[https://hxim.github.io/Stockfish-Evaluation-Guide/ Stockfish Evaluation Guide]</ref> ==Classical [[Evaluation]]== Classical Evaluation (traditional hand-crafted evaluation) has been removed since version 16.

==2008==* Stockfish 1.0 : - November 02, 2008* Stockfish 1.01 : - November 03, 2008* Stockfish 1.1 : - December 06, 2008* Stockfish 1.1a : - December 08, 2008* Stockfish 1.2 : - December 29, 2008==2009==* Stockfish 1.3 : - May 02, 2009* Stockfish 1.3.1 : - May 03, 2009* Stockfish 1.4 : - July 05, 2009* Stockfish 1.5 : - October 04, 2009* Stockfish 1.5.1 : - October 11, 2009* Stockfish 1.6 : - December 25, 2009* Stockfish 1.6.1 : - December 25, 2009* Stockfish 1.6.2 : - December 31, 2009==2010 ...==* Stockfish 1.6.3 : - February 02, 2010* Stockfish 1.7 : - April 08, 2010* Stockfish 1.7.1 : - April 10, 2010* Stockfish 1.8 : - July 02, 2010* Stockfish 1.9 : - October 02, 2010* Stockfish 1.9.1 : - October 05, 2010'''2011'''* Stockfish 2.0 : - January 01, 2011* Stockfish 2.0.1 : - January 04, 2011* Stockfish 2.1 : - May 04, 2011* Stockfish 2.1.1 : - May 08, 2011* Stockfish 2.2 : - December 29, 2011'''2012'''* Stockfish 2.2.1 : - January 06, 2012* Stockfish 2.2.2 : - January 14, 2012* Stockfish 2.3 : - September 15, 2012* Stockfish 2.3.1 : - September 22, 2012'''2013'''* Stockfish 3 : - April 30, 2013* Stockfish 4 : - August 20, 2013* Stockfish DD : - November 29, 2013* Stockfish 5 : - May 31, 2014==2015 ...==* Stockfish 6 : - January 27, 2015* Stockfish 7 : - January 02, 2016* Stockfish 8 : - November 01, 2016* Stockfish 9 : - February 01, 2018* Stockfish 10 : - November 29, 2018==2020 ...==* Stockfish 11 - January 18, 2020* [[Stockfish NNUE|Stockfish 12]] - September 02, 2020* Stockfish 13 - February 19, 2021* Stockfish 14 - July 02, 2021* Stockfish 15 - April 18, 2022* Stockfish 15.1 - December 04, 2022* Stockfish 16 - June 30, 2023* Stockfish 16.1 - February 24, 2024

* [[DONShashChess]]

 =Videos= * [[Daylen Yang#Video|How do modern chess engines work? | VideoBill Jordan]], Talk by [[Daylen Yang]], ('''2020'''). ''Calculation versus Intuition: Stockfish versus Leela''. [httphttps://www.tngtechamazon.com/tngCalculation-versus-ueberIntuition-uns/bigtechday/bigStockfish-techdayLeela-8.html TNG | Big Techday 8], June 12, 2015* [[Tord Romstad#Video|Parallelism and Selectivity in Game Tree Search | Video]], Talk by [[Tord Romstad]], [http:ebook/dp/www.tngtech.com/tng-ueber-uns/bigtechdayB08LYBQDMB/big-techday-8.html TNG | Big Techday 8amazon], June 12, 2015* » [[Tord Romstad#Video|How Modern Chess Programs Work | VideoTCEC]] by , [[Tord RomstadLeela Chess Zero]], [http://2017.flatmap.no/talks/romstad/ flatMap(Oslo)], May 02, 2017

* [http://www.talkchess.com/forum/viewtopic.php?t=39214 Stockfish clones in the AppStore: it's becoming a plague...] by [[Julien Marcel]], [[CCC]], May 28, 2011 » [[:Category:Clone|Clones]]

* [http://www.talkchess.com/forum/viewtopic.php?t=49854 Stockfish search] by [[Harm Geert Muller]], [[CCC]], October 28, 2013 » [[Principal variationVariation]]

* [http://www.talkchess.com/forum/viewtopic.php?t=52117&start=1 Huge simplification] by [[Lyudmil Tsvetkov]], [[CCC]], April 25, 2014 » [[Pawn chainChain]]

* [http://www.talkchess.com/forum/viewtopic.php?t=54750 Stockfish and accurate PV] by [[Matthew Lai]], [[CCC]], December 25, 2014 » [[Principal variationVariation]]

* [http://www.talkchess.com/forum/viewtopic.php?t=61250 Stockfish eval output] by [[Erin Dame]], [[CCC]], August 27, 2016 » [[Wrong color Color Bishop and rook pawnRook Pawn]]

* [https://groups.google.com/forum/#!topic/fishcooking/AE4EgWQ20dY A branch to test the Monte Carlo algorithm in Stockfish] by [[Stephane Nicolet]], [[Computer Chess Forums|FishCooking]], December 06, 2017 » [[Monte-Carlo Tree Search]], [[AlphaZero]]

* [https://groups.google.com/d/msg/fishcooking/_FW_RIowarw/y1e-qMEXAgAJ Contributors in the last two years] by [[Stephane Nicolet]], [[Computer Chess Forums|FishCooking]], Jnauary 30, 2018

==Chess engineEngine==

: * [https://githubnextchessmove.com/zamar/spsa SPSA Tuner for dev-builds NCM Stockfish Chess Engine] » [[SPSA]Dev Builds]* [httphttps://abrok.eu/stockfish/ Stockfish Development Versions] hosted by [[Roman Korba]]* [https://stockfishchess.de/ Stockfish Development Versions for macOS]* [http://blog.stockfishchess.org/ Stockfish Blog]* [http://twitter.com/stockfishchess stockfishchess] on [https://en.wikipedia.org/wiki/Twitter Twitter]

==Issues==* [httphttps://wwwgithub.chess.fortherapy.co.ukcom/official-stockfish/Stockfish/issues Issues · official-stockfish/ Arduino & Raspberry PI Chess Computer] running [[Stockfish]] on [[Raspberry Pi]], by [[Max Dobres]] » [[Arduino]], [[Sensory Board]· GitHub]* [httphttps://techgithub.mit.educom/official-stockfish/V133Stockfish/N62issues/chess.html One chess champion per laptop2823 NNUE merge · Issue #2823 · official-stockfish/Stockfish · GitHub] by [[Joost VandeVondele]], July 25, 2020 <ref>[http://www.mittalkchess.educom/~robertoforum3/ Roberto Perez-Francoviewtopic.php?f=2&t=74560 An info]by Sylwy, [[Massachusetts Institute of Technology|MIT'sCCC]] , July 25, 2020</ref>* [https://engithub.wikipedia.orgcom/official-stockfish/Stockfish/issues/wiki2915 NNUE ideas and discussion (post-merge) Issue #2915 official-stockfish/The_Tech_%28newspaper%29 The TechStockfish · GitHub], January 15, 2014 » by [[TCEC Season 5Joost VandeVondele]], August 06, 2020* [httphttps://en.chessbasegithub.com/postofficial-stockfish/Stockfish/issues/john3021 NNUE eval rotate vs mirror · Issue #3021 · official-hartmann-and-then-there-were-two And then there were twostockfish/Stockfish · GitHub] by [http[Terje Kirstihagen]], August 18, 2020==Pull Requests==* [https://en.chessbasegithub.com/authorofficial-stockfish/Stockfish/johnpulls Pull requests · official-hartmann John Hartmann], [[ChessBase|ChessBase News]], June 09, 2015 » [[Komodo]], [[stockfish/Stockfish]· GitHub]* [https://rjlipton.wordpressgithub.com/2015official-stockfish/10Stockfish/06pull/depth3474 Update default net to nn-of8a08400ed089.nnue by Sopel97 · Pull Request #3474 · official-satisficingstockfish/ Depth of SatisficingStockfish · GitHub] by [[Kenneth WTomasz Sobczyk]]==Testing==* [https://stockfishchess. Regan|Ken Reganorg/get-involved/ Get Involved - Stockfish - Powerful Open Source Chess Engine]], * [https://rjliptontests.wordpressstockfishchess.comorg/ Gödel's Lost Letter and P=NPtests Stockfish Testing Framework], October 06, 2015 » [[DepthStockfish#Fishtest|Fishtest]], * [[Match Statisticshttps://hxim.github.io/Stockfish-Evaluation-Guide/ Stockfish Evaluation Guide]], [[Pawn Advantage, Win Percentage, and Elo]], » [[Stockfish#EvaluationGuide|Stockfish Evaluation Guide]], : [[Komodo]] <ref>[httphttps://wwwhxim.talkchessgithub.comio/forumStockfish-Evaluation-Guide/viewtopic.php?tp=57890 Regan's latest: Depth of Satisficingnnue Stockfish Evaluation Guide - NNUE] by Carl Lumma, * [[CCC]https://github.com/glinscott/fishtest GitHub - glinscott/fishtest: Stockfish testing], October 09, 2015</ref>* : [https://rjlipton.wordpressgithub.com/2016glinscott/01fishtest/21wiki/aCreating-chessmy-firewallfirst-attest Creating my first test · glinscott/fishtest Wiki · GitHub]: [https://github.com/glinscott/fishtest/wiki/Fishtest-zeromathematics Fishtest mathematics · glinscott/fishtest Wiki · GitHub]* [https:// A github.com/zamar/spsa SPSA Tuner for Stockfish Chess Firewall at Zero?Engine] by » [[Kenneth W. Regan|Ken ReganSPSA]], * [https://rjliptongroups.wordpressgoogle.com/ Gödel's Lost Letter forum/#!forum/fishcooking FishCooking - Google Groups] a discussion group for developers and P=NPtesters of [[Stockfish]], January 21, 2016chess engine

* [http://www.computerchess.org.uk/ccrl/4040/cgi/compare_engines.cgi?family=Stockfish&print=Rating+list&print=Results+table&print=LOS+table&print=Ponder+hit+table&print=Eval+difference+table&print=Comopp+gamenum+table&print=Overlap+table&print=Score+with+common+opponents Stockfish] from [[CCRL|CCRL 40/4015]]* [http://computerchess.org.uk/ccrl/404/cgi/engine_detailscompare_engines.cgi?family=Stockfish&print=Rating+list&print=Results+table&print=LOS+table&print=Ponder+hit+table&print=DetailsEval+difference+table&each_gameprint=1Comopp+gamenum+table&engprint=Overlap+table&print=Score+with+common+opponents Stockfish%205%2064-bit%204CPU#Stockfish_5_64-bit_4CPU Stockfish 5 64-bit 4CPU] in [[CCRL|CCRL 40/4Blitz]]

* [http://www.chess.com/article/view/how-rybka-and-i-tried-to-beat-the-strongest-chess-computer-in-the-world Can a GM and Rybka beat Stockfish?] by GM [https://en.wikipedia.org/wiki/Daniel_Naroditsky Daniel Naroditsky], [https://en.wikipedia.org/wiki/Chess.com [Chess.com]], August 08, 2014 » [[Stockfish#Matches|GM+Rybka vs. Stockfish]]* [http://www.chess.com/news/stockfish-outlasts-nakamura-3634 Stockfish Outlasts "Rybkamura"] by [http://www.chess.com/article/view/chesscom-player-profiles-fm-mikeklein FM Mike Klein], [https://en.wikipedia.org/wiki/Chess.com [Chess.com]], August 24, 2014* [https://www.chess.com/news/view/alphazero-reactions-from-top-gms-stockfish-author AlphaZero: Reactions From Top GMs, Stockfish Author] by [http://www.chessvibes.com/?q=peterdoggers [Peter Doggers]], [https://en.wikipedia.org/wiki/Chess.com [Chess.com]], December 08, 2017 » [[AlphaZero#StockfishMatch|AlphaZero vs. Stockfish]]