Top 10 Strongest Chess Engines In 2021

According to studies, chess has a total of 10120 possible moves. These are so many moves for the human mind to comprehend. Chess has been around for over 1400 years and continues to improve with the growth of technology and the passage of time.

Today, chess engines are used to analyze the millions of possible outcomes in a bid to come up with the most efficient moves. Chess engines have been around for several decades and they continue to get better with the growth of technology.

The engines are now more selective and have better understanding of different chess positions. In this article, we analyze the top 10 strongest chess engines in 2021.

How Chess Engines are Rated

Before diving into the top 10 list of the strongest chess engines in 2021, it is important to know how these engines are rated. Very many chess engines’ rating lists are available.

The rating lists are based on the number of moves they can make per minute and their margins of error.

The most famous rating lists include Computer Chess Rating Lists (CCRL) and Chess Engines Grand Tournament (CEGT). We use these rating lists to present to you the best chess engines that have surpassed and dominated humanity.

Top 10 Strongest Chess Engines In 2021

10. Xiphose

Xiphose has a CCRL rating of 3324 and CEGT rating of 3193. Distributed under General Public License (GNU), Xiphos is an open-source chess engine written in C. Under the watchful eye of PEXT bitboards or magic bitboards, this chess engine can run on Windows, Mac OS, and Linux operating systems.

9. Shredder

Developed in 1993, Shredder is a chess engine with a CCRL rating of 3324 and a CEGT rating of 3153. It has been able to withstand the test of time through its constant success and the ability to get the job done.

Since its inception, this search engine has won over 20 titles which include the World Microcomputer Chess Championship held in 1996 and 200. Shredder has also won double World Computer Chess Championships, a World Chess Software Championship and 5 times World Computer Speed Championships.

Shredder is supported by Mac OS, Windows and Linux operating systems. Its graphical interface is top-notch, which comes as a little surprise considering that it was developed by the legendary Millennium Chess System.

8. Boot

With CCRL rating of 3326 and CEGT rating of 3234, Boot chess engine is one of the strongest in the universe. Written in Delphi 6, this chess engine figures sliding piece attacks with rotated bitboards.

It comes with a lazy SMP and its evaluation function is fully redesigned. To rank amongst the best, this chess engine solves problems such as decreasing late moves, deepening internal iterative and prunes null moves.

It has multiple processors that can support computers with both 32 and 64 bit processors.

7. Rybka

Chess Master Vasik Rajlich is responsible for designing this chess engine. From 2007 to 2012, Rybka was a force to reckon. It has single-handedly won many computer chess tournaments and continues to do so up to today.

In the period between 2007 and 2010, this search engine won four consecutive World Computer Chess Championships even though the titles were later stripped for plagiarism.

However, the International Computer Games Association (ICGA) ordered Rajlich to merge with ChessBases late in 2015.

6. Stockfish

Stockfish has a CCRL rating of 3390. It is an open source UCI chess engine and it is available for free for chess gamers. The software works perfectly for both mobile devices and desktops.

The chess engine has been dominant since 2014 and has won several world computer chess championships between then and now.

5. Andscacs

Even though it was developed in 2014, this chess engine quickly grew into a force to reckon. Its main stronghold is the ability to speed up the attack calculations and come up with perfect results. It uses the principal variation search with the aid of a transposition table inside an iterative framework.

To make Andscacs more powerful, chess researchers came up with 200 evaluation features that encompassed 750,000 positions.

4. Fire

With a CCRL rating of 3430 and CEGT rating of 3319, Fire is one of the best chess engines currently in the market. At first, Fire was an open source chess engine. However, that quickly changed into a closed Windows and is only available for brand new Intel processors.

When it was first developed, this chess engine was known as Firebird but was later changed to Fire because there was a conflict in the trademark name. Even with all these internal changes, Fire continues to scale new heights and it is definitely one of the best chess engines in 2021.

3. Komodo

Developed by Don Dailey and Mark Lefler, Komodo is a chess engine with CCRL rating of 3508 and CEGT rating of 3424. Today, Komodo is a commercial chess engine but its older versions are available for free. Komodo ranks amongst the best because of its ability to find moves in situations where other chess engines struggle. Chess players claim that it sets them up to win.

2. Houdini

Houdini has a CCRL rating of 3529 and CEGT rating of 3444. It is famous for its positional style and the ability to build strong defenses. To date, Houdini has won the Top Chess Engine Championship 3 times and continues to scale new heights.

1. Leela Chess Zero

Leela Chess Zero chess engine has a CCRL rating of 3463 and CEGT rating of 3467. It ranks amongst the best because of its ability to rely on self-taught neural networks to make superb chess moves. The chess engine learns from itself by playing against itself as many times as possible.


Coming up with a list of the top 10 strongest chess engines is not easy considering that they continue to evolve with the growth of technology. However, we have managed to come up with the above list after researching and analyzing the chess engines’ best features as it stands.

Chess engines are beneficial because they can analyze the many possible moves that chess presents and come up with the best options.