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a chess engine by primary author [[Don Dailey]] (died at the age of 57 on November 22, 2013) and since October 2013, by [[Mark Lefler]], supported by chess advisor and evaluation expert and Don's long time collaborator [[Larry Kaufman]]. Since 2015, [[:Category:Opening Book Author|opening book expert]] [[Erdogan Günes]] is responsible for Komodo's [[Opening Book|book moves]].

As of December 2011, Komodo became commercial with version '''4''' <ref>[http://komodochess.com/komodo4sp-28a Komodo 4 UCI chess engine download]</ref>, earlier versions running under [[Windows]], [[Linux]], [[Mac OS]] and [[Android]] are available from the Komodo download site, free for non-commercial use <ref>[https://komodochess.com/downloads.htm Available Versions of Komodo]</ref> <ref>[http://komodochess.com/downloads.php Komodo chess engine by Don Dailey and Larry Kaufman - Downloads]</ref>. Next release date was May 2013, with [[CCT15]] winner Komodo '''CCT''' <ref>[http://www.talkchess.com/forum/viewtopic.php?t=47906 Komodo CCT release] by [[Don Dailey]], [[CCC]], May 03, 2013</ref>.

As winner of the TCEC 5 final, Komodo '''TCEC''' was released on December 04, 2013 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=50324 Komodo TCEC released] by [[Larry Kaufman]], [[CCC]], December 04, 2013</ref>, the further improved Komodo '''7''' on May 21, 2014, during the [[TCEC Season 6#Superfinal|TCEC Season 6 final]] versus [[Stockfish]] again, now supporting [[Syzygy Bases]] <ref>[http://komodochess.com/Komodo7-38a.htm Komodo chess engine - Komodo 7]</ref>, probing code interface implementation by [[Jeremy Bernstein]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=52391&start=7 Re: Komodo Syzygy evals] by [[Larry Kaufman]], [[CCC]], May 21, 2014</ref>.

Komodo '''8''', released on September 05, 2014, is was a substantial improvement over Komodo 7a, which was already rated among the top three chess engines on almost all rating lists <ref>[http://komodochess.com/Komodo8-40a.htm Komodo chess engine - Komodo 8]</ref>. Komodo 8 supports [[Syzygy Bases]] and is available for [[Windows]], [[Linux]], [[Mac OS]] and [[Android]], the latter immediately available for import in [[Chess for Android]] and in [[Chess for Glass]] <ref>[http://aartbik.blogspot.de/2014/09/more-on-komodo-8.html More on Komodo 8] by [[Aart Bik]], September 9, 2014</ref>. Since mid September 2014, Komodo 8 for Windows is available as [[ChessBase]] engine, bundled with the [[Fritz#DeepFritz14|Deep Fritz interface]], Syzygy bases not included <ref>[http://shop.chessbase.com/en/products/komodo_chess_8 Komodo 8] - [[ChessBase|ChessBase Shop]], September 10, 2014</ref>.

Komodo '''9''', released on April 28, 2015, continues continued the progress with approximately +50 Elo over Komodo 8 due to improved [[Search|search]], [[Evaluation|evaluation]], and [[Time Management|time management]], as well as more efficient use of multiprocessing <ref>[http://komodochess.com/Komodo9-43a.htm Komodo chess engine - Komodo 9]</ref>. Most noticeable is the increase in [[Depth|search depth]] reached in a given amount of time, which is due to better [[Extensions|extension]], [[Reductions|reduction]], and [[Pruning|pruning]] rules <ref>[http://www.talkchess.com/forum/viewtopic.php?t=56092 Komodo 9 Announcement] by [[Larry Kaufman]], [[CCC]], April 22, 2015</ref>. Further, Komodo 9 now features [[Chess960]] and a [[Persistent Hash Table|persistant hash]] to save and restore analysis.

implementing MCTS was already an old idea of the Komodo team - also due to [[Don Dailey|Don Dailey's]] computer [[Go]] experience in developing a MCTS building an [[GoUCT]] programmingplayer.<span id="MCTS"></span>==Komodo MCTS==In Komodo's [[Monte-Carlo Tree Search|MCTS ]] mode the [[Search Tree|search tree]] is expanded in [[Best-First|best-first]] manner based on [[Pawn Advantage, Win Percentage, and Elo|winning probabilities]] determined not neither by random playoutsnor by a [[Neural Networks|neural network]], but a tiny [[Alpha-Beta|alpha-beta search]] plus [[Quiescence Search|quiescence]] and [[Evaluation|static evaluation]], also similar to [[UCT]], dealing with the with crucial trade-off between [https://en.wikipedia.org/wiki/Monte_Carlo_tree_search#Exploration_and_exploitation exploration and exploitation]. While [[Playing Strength|playing strength]] is lower with MCTS, positional play and judgement may well be better in many positions <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=2&t=67441 Komodo 12 and MCTS] by [[Larry Kaufman]], [[CCC]], May 14, 2018</ref>, not to mention a more risky and entertaining playing style.<span id="13"></span>==Komodo 13==In May 2019, Komodo '''13''' was released with substantial improvements in [[Monte-Carlo Tree Search|MCTS]] mode. Quote by [[Larry Kaufman]] <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=2&t=70681&start=77 Re: Komodo 13 released] by [[Larry Kaufman]], [[CCC]], May 18, 2019</ref>: The changes from Komodo 12 to 13 in MCTS mode (which is where most of the changes were made) are so vast and pervasive that it is hopeless to even try to enumerate them. The elo gains are in the 300 to 400 range on any number of threads, so it's really a very different engine. Virtually every aspect was improved, some of the changes being rather radical. Most cannot be explained without describing in detail how Komodo MCTS works, which is pretty unique. As for regular Komodo, there were quite a few changes, but only a few that show up as measurable elo gains on one to four threads. To be honest, if you never use [[Principal Variation#MultiPV|MultiPV]] or MCTS mode, don't have more than a few cores, and already own Komodo 12, I wouldn't recommend spending the money for Komodo 13 unless the cost is insignificant to you. But I think that most people do use MultiPV, and if so Komodo 13 MCTS is clearly better than Komodo 12 in either mode.<span id="14"></span>==Komodo 14==Komodo '''14''', released in May 2020 with following improvements announced by [[Larry Kaufman]] <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=2&t=73916 Komodo 14 released] by [[Larry Kaufman]], [[CCC]], May 12, 2020</ref>: The improvements cover a wide range of issues, including [[Extensions|extensions]], [[Null Move Pruning|null move]], [[King Safety]], [[Time Management|time management]], and many more. There is one new feature added since Komodo 13.3, "[https://en.wikipedia.org/wiki/Fast_chess#Armageddon Armageddon]" mode, which tells Komodo that White (or Black) must win, draws are scored as losses for that color. When draws are counted as losses for White, knowing this improves Komodo's performance as White by about 30 elo according to our tests. In Armageddon mode, the specified color (usually White) not only avoids clear draws, but adjusts [[Contempt Factor|Contempt]] by an amount we determined was most helpful for Armageddon play. Testing on one thread in Armageddon mode suggests that on a modern laptop, if White gets one minute total plus 1% increment, and Black gets half a minute plus 1% increment plus draw odds, then chances are fairly close to balanced. Other features added since Komodo 13 include more levels, Personalities, and Auto-Skill. Standard mode remains the strongest when [[Principal Variation#MultiPV|Multi-PV]] is not in use, while [[Monte-Carlo Tree Search|MCTS]] mode is generally strongest when both are using Multi-PV.

In [[Timeline#2018|2018]] [[#12|Komodo 12]] continued its success by winning the [[ICGA]] [[WCCC 2018]], [[WCSC 2018]] and Blitz tournaments in [https://en.wikipedia.org/wiki/Stockholm Stockholm], and later that year the [[WCRCC 2018]] online.===2019===[[Komodo#13|Komodo 13.1]] <ref>[http://www.talkchess.com/forum3/viewtopic.php?f=2&t=71606 Komodo 13.1 released] by [[Larry Kaufman]], [[CCC]], August 19, 2019</ref> was able to defend both titles at the [[ICGA]] [[WCCC 2019]] and [[WCSC 2019]] in [https://en.wikipedia.org/wiki/Macau Macau], the WCCC on a 128 cores.

Komodo pushes the selectivity pretty hard and we DO get a decent [[Nodes per secondSecond|nodes per second]] increase with Lazy evaluation but the problem is that we get a big increase in [[Node|nodes]]. It is this way because we assume we will not make scout if the guesstimate is too low. So we miss some of the [[Beta-Cutoff|beta cutoffs]], you cannot have your cake and eat it too. Komodo's positional component can vary enormously so we do take a lot of damage positionally when we use lazy margins.

* [[Tamal T. Biswas]], [[Kenneth Wingate Regan|Kenneth W. Regan]] ('''2015'''). ''Measuring Level-K Reasoning, Satisficing, and Human Error in Game-Play Data''. [[IEEE]] [http://www.icmla-conference.org/icmla15/ ICMLA 2015], [http://www.cse.buffalo.edu/~regan/papers/pdf/BiRe15_ICMLA2015.pdf pdf preprint]

* [http://www.talkchess.com/forum/viewtopic.php?t=53813 Komodo Android Experiment] by [http://www.talkchess.com/forum/profile.php?mode=viewprofile&u=608 [Ted Summers]], [[CCC]], September 24, 2014

* [https://rjlipton.wordpress.com/2015/10/06/depth-of-satisficing/ Depth of Satisficing] by [[Kenneth Wingate W. Regan|Ken Regan]], [https://rjlipton.wordpress.com/ Gödel's Lost Letter and P=NP], October 06, 2015 » [[Depth]], [[Match Statistics]], [[Pawn Advantage, Win Percentage, and Elo]], [[Stockfish]], [[Komodo]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=57890 Regan's latest: Depth of Satisficing] by Carl Lumma, [[CCC]], October 09, 2015</ref>* [https://rjlipton.wordpress.com/2016/01/21/a-chess-firewall-at-zero/ A Chess Firewall at Zero?] by [[Kenneth Wingate W. Regan|Ken Regan]], [https://rjlipton.wordpress.com/ Gödel's Lost Letter and P=NP], January 21, 2016

* [https://komodochess.com/Komodo12.htm Komodo chess engine - Komodo 1213]

* [https://shop.chessbase.com/en/products/komodo_chess_12 komodo_chess_13?Ref=RF70-5OH0EFN840 Komodo 1213] - [[ChessBase|ChessBase Shop]], May 20182019

* [https://rjlipton.wordpress.com/2014/12/28/the-new-chess-world-champion/ The New Chess World Champion] by [[Kenneth Wingate W. Regan|Ken Regan]], [http://rjlipton.wordpress.com/ Gödel's Lost Letter and P=NP], December 28, 2014 » [[Larry Kaufman]], [[TCEC Season 7]]

* [https://en.chessbase.com/post/komodo-8-the-smartphone-vs-desktop-challenge Komodo 8: the smartphone vs desktop challenge] by [[Albert Silver]], [[ChessBase|ChessBase News]], September 24, 2014 <ref>[http://www.talkchess.com/forum/viewtopic.php?t=53813 Komodo Android Experiment] by [http://www.talkchess.com/forum/profile.php?mode=viewprofile&u=608 [Ted Summers]], [[CCC]], September 24, 2014</ref>

'''Komodo 12/MCTS'''