Ever since GM Garry Kasparov lost against Deep Blue in 1997, computer engines have dominated the game of chess, proving themselves beyond any human sphere.
When it comes to the strongest chess engines, though, Stockfish, Leela Chess Zero, Komodo, Houdini, and Shredder stand on top.
These engines have defeated the best players in the world, and they continue to evolve and make inspiring plays to this day.
So, how do they stack against each other? What makes each one of them unique? In this article, we’ll answer all these questions and more.
What Is a Chess Engine?
A chess engine is a piece of software that analyzes the position of every piece on the board to come up with the best next move.
Its learning and growing abilities surpass those of any human. Most of the engines on this list have an ELO rating of more than 3000.
Even Magnus Carlsen, the top-rated chess player in the world today, hasn’t come close to that rating yet. So, that should give an idea of how strong they are.
What Are the Best 5 Chess Engines?
Let’s see which engines stand on top of the chess world and what makes them so special.
This one’s a no-brainer. No chess engine has had an impact on the chess world like Stockfish.
One of Stockfish’s strongest advantages is that its development is community-based. Not only does the Stockfish team work to improve the engine, but they also allow the entire chess community to contribute to its growth.
For example, they created the fishtest, in which enthusiasts of the engine can let their computers play chess games against new versions of the engine in the background. This allows the team to identify the engine’s weaknesses, and make adjustments accordingly.
Moreover, the Stockfish team is constantly thinking of innovative ways to make the engine stronger. In 2020, for example, they integrated an efficiently updatable neural network into their engine.
This integration increased Stockfishe’s evaluative abilities more than tenfold. In fact, in one month, the engine has gone through two years’ worth of development.
Stockfish has dominated numerous computer competitions over the years. Since 2013, it’s won the Top Chess Engine Championships (TCEC) 14 times, beating Leela Chess Zero, Houdini, and Komodo.
Even in chess variants, Stockfish has proven itself head and shoulders above the other engines. It won the Fischer Random tournament in 2014 and the 10th TCEC Rapid tournament.
With an ELO of over 3500, Stockfish is recognized by many as the best chess engine in the world.
Leela Chess Zero
Leela Chess Zero (Lc0) has made a strong impression since its first appearance in 2018. That’s because it was inspired by AlphaZero.
When AlphaZero defeated Stockfish repeatedly, the chess world was excited to see what it’ll offer the game. Unfortunately, though, it wasn’t available to the public. That’s when Leela Chess Zero came in.
What sets Leela Chess Zero apart from the other engines is that it was the first accessible neural network engine to be introduced to the public.
It uses the same reinforcement learning method that AlphaZero used to teach its neural networks how to play chess.
In other words, the developers fed the rules of the game to the engine and let it learn chess by playing millions of games against itself.
The engine learns from its wins and losses and uses that knowledge against its opponents.
In a few months, Leela Chess Zero reached the highest levels of chess mastery. It also gave other engines a run for their money.
In the 14th TCEC, it secured second place, losing only to Stockfish in the superfinal. Despite the loss, the score was pretty close 50.5-49.5.
So, even at its earliest stages, Leela held its own against the top-rated chess engine in the world. The first big milestone Lc0 crossed was in 2019 when it won the TCEC cup twice.
In the February tournament, it defeated Houdini to claim its first victory. Then, it’d go on to defeat Stockfish in May.
Because of its neural network-based build, Leela Chess Zero evaluates the board differently. It makes more unconventional moves than other conventional engines. That’s why it’s an overwhelmingly powerful engine.
As weird as this is going to sound, GM Larry Kaufman, one of the supervisors of this engine, developed Komodo to play like humans.
Kaufman noticed that chess engines were tactically superior to humans. However, Top chess players still excelled in positional plays.
Because he wanted the engine to combine its automated prowess with accepted human chess theory, the Komodo team developed it to play in a distinctive positional style.
That means Komodo is more invested in properly developing its pieces and slowly building pressure on the opponent’s king. It also means it’s not afraid to make positional sacrifices, which is not something a lot of engines are willing to make.
This playing style makes Komodo more versatile than other chess engines. It opens the gate for potential strategies that other engines wouldn’t come up with.
Three years after it was introduced, Komodo defeated Stockfish in the fifth season of TCEC’s superfinal. It went on to do it again in 2014 and 2015.
It also won the World Computer Chess Championship five times and the World Computer Software Championship three times, along with numerous other computer tournaments.
Houdini is one of the strongest chess engines money can buy. Just like Komodo, it uses a positional playing style. That’s why it’s called Houdini in the first place.
Generally, Houdini was built to be an all-rounder. In fact, Robert Haudart, the engine’s developer, used Stockfish and Crafty as references when he created it.
Of course, he improved upon them however he saw fit. With each new version, the engine displayed a better understanding of the various aspects of the game.
Houdini made its name with an explosive victory in two TCECs in 2010. It was even able to defeat Stockfish in 2013 to win the fourth TCEC.
Houdini would then go on to win first place and second place in many tournaments, proving itself capable of competing against the best engines in the world.
Although it’s one of the oldest chess engines in the world, Shredder has stood the test of time. The name gives away the engine’s attitude toward its competitors.
It currently has three versions: Shredder Classic 5, Shredder 13, and Deep Shredder 13. The Classic version is the simplest one and the Deep version is the most advanced.
Shredder is one of the most user-friendly chess engines on this list. If you want to practice playing against a specific style, you can easily customize the computer to play that style.
It has a lot of features, like the “coach” mode, that can help you avoid making wrong moves.
Being one of the oldest engines on this list, it’s no surprise that Shredder won the World Computer Chess Championship 19 times. From 2005 to 2007, it dominated the Computer Blitz World Championship.
Now you know what the top 5 strongest chess engines are. Every one of these engines brings something different to the table.
So, whether you want to improve in general or practice playing against a specific style, you can choose the engine that meets your needs the most.