GAN11 M Pro, a 3x3 Rubik's Cube designed for speedcubing
Speedcubing, also referred to as speedsolving, is a competitive sport centered around the rapid solving of various combination puzzles. The most prominent puzzle in this category is the 3x3x3 puzzle, commonly known as the Rubik's Cube. Participants in this sport are known as "speedcubers," who focus specifically on solving these puzzles at high speeds, or more generally as "cubers". The essential aspect of solving these puzzles typically involves executing a series of predefined algorithms in a particular sequence.
Competitive speedcubing is predominantly overseen by the World Cube Association (WCA),[1] which, as of January 16, 2024, officially recognizes 17 distinct speedcubing events. These events encompass a range of puzzles, including cubic puzzles of sizes ranging from 2x2 to 7x7 and other puzzle forms such as the Pyraminx, Megaminx, Skewb, Square-1, and Rubik's Clock. Additionally, specialized formats such as 3x3, 4x4, and 5x5 blindfolded, 3x3 one-handed, 3x3 fewest moves, and 3x3 multi-blind are also regulated and hosted in competitions.[1]
As of July 2023, the world record for the fastest single solve of a Rubik's cube in a competitive setting stands at 3.13 seconds. This record was achieved by Max Park at the Pride in Long Beach 2023 event on June 11, 2023.[2][3] Additionally, Yiheng Wang set the record for the average time of five solves in the 3x3x3 category at 4.48 seconds at Mofunland Cruise Open 2023 on June 20, 2023.[4][5] Speedcubing participants are predominantly under the age of 20, and numerous countries organize international competitions throughout the year.[6] The widespread popularity of the Rubik's Cube has led to an abundance of online resources, including guides and techniques, aimed at assisting individuals in solving the puzzle.
History
Original Rubik's cube from 1980
The Rubik's Cube was invented on May 19, 1974, by Hungarianprofessor of architectureErnő Rubik (born July 13, 1944). In 1979, Rubik partnered with Ideal Toy Company to garner widespread international interest in the cube. On June 5, 1982, the first world championship of speedcubing was held in Budapest, Hungary. Nineteen people competed in the event, and the American Minh Thai won with a single solve time of 22.95 seconds, which was, at the time, the fastest Rubik's Cube solve ever recorded. Other attendees include Jessica Fridrich and Lars Petrus, both of whom later contributed to the development of new solving methods and of the speedcubing community.[7] The Rubik's Cube waned in popularity after 1983, as there were no official competitions held,[8] but with the advent of the Internet, online websites began to surface to discuss the cube. With these websites facilitating the renewed popularity of the cube, a new generation of speedcubers arose.
Those prominent in the online speedsolving community, such as Ron van Bruchem, Tyson Mao, Chris Hardwick, and Ton Dennenbroek, eventually wanted to create an organization where cubers from around the world could meet and compete. In 2003, they organized a championship in Toronto, Ontario, followed by another competition in the Netherlands later that same year. This revival of competition sparked a new wave of organized speedcubing events, which included regular national and international competitions.[9] There were twelve competitions in 2004, 58 more from 2005 to 2006, over 100 in 2008, and over 1150 in 2018. Since Budapest's 1982 competition, there have been nine further World Championships traditionally held every other year. This new wave of speedcubing competitions has been and still is organized by the World Cube Association (WCA).
Since the rise of speedcubing's popularity, numerous entrepreneurial ventures have been founded specializing in making or selling speedcubes, creating competition between these brands and Rubik's. Dozens of cube manufacturers, such as GANCube, MoYu, YJ, and QiYi, have begun improving the cube's technology to allow for smoother turning and faster solving.[10] This has helped to facilitate the eventual rise of the Rubik's Cube as not just a toy, but also a lucrative business.[11]
Solving methods for 3x3x3 Cubes
The standard 3x3x3 can be solved using several methods, not all of which are intended for or suited to speedcubing. The most commonly used methods for speedcubing are CFOP, Roux and ZZ, which are generally considered to achieve the fastest times. The CFOP method is used by the majority of cubers and employs a layer-by-layer system with numerous algorithms for solving the final layer. Roux, the second most popular method, starts by forming a 3x2x1 block on either side of the cube and solves the middle layer last, using fewer algorithms. ZZ uses a unique step called Edge Orientation to improve the ergonomics of turning. Other notable methods include Petrus, which has been popular at times in the past; however, it is now considered sub-optimal to CFOP and Roux and was abandoned due to its unfavorable fingertricks.
Solving larger cubes, such as 4x4x4 and 5x5x5, is most often done by reducing them to 3x3x3 and solving them like so, while 2x2x2 can be solved with the same or similar methods as 3x3x3. However, specialized 2x2x2 methods are quicker, and are regarded as superior to 3x3x3 methods. These methods include Ortega, CLL, and one-look solves with the EG method.
The CFOP (abbreviation for Cross-F2L-OLL – PLL) method, also known as the Fridrich method after one of its inventors, Jessica Fridrich, who finished second in the 2003 Rubik's Cube World Championships, is the most commonly used method in speedcubing today. Its origins are credited to David Singmaster, who was one of the first to publish a layer-by-layer method of solving in 1980,[12] and Guus Razoux Schultz, who built upon this and developed a more efficient system for the first two layers (F2L).[13] Jessica Fridrich then finished developing the method and published it online in 1997,[14] an event that was very influential in the revival of competitive speedcubing. The first step of the method is to solve a cross of edge pieces on the first layer. The remainder of the first layer and all of the second layer are then solved together in what is referred to as "corner-edge pairs," or slots. Finally, the last layer is solved in two steps – first, all of the pieces in the layer are oriented to form a solid color (but without the individual pieces always being in their correct places on the cube). This step is referred to as orientation and is usually performed with a single set of algorithms known as OLL (Orientation of the Last Layer). Then, all of those pieces are permuted to their correct spots. This is also usually performed as a single set of PLL (Permutation of the Last Layer) algorithms. OLL and PLL use 57 and 21 algorithms, respectively.
The CFOP method can be used as a less advanced method by dividing the steps into more steps, reducing the number of algorithms that need to be learned but sacrificing time. It is usually known as the beginner method or layer by layer (LBL). Most people start learning CFOP with 4LLL (Four-Look Last Layer), which is the less advanced, slower, and algorithm-reducing (from 78 algorithms to 16) way to learn CFOP. The 4 steps are divided into edge orientation, corner orientation, corner permutation, and edge permutation (which can be called EO, CO, CP, and EP). Later on, full OLL, which has 57 algorithms, and full PLL, which has 21 algorithms, can be learned. An average CFOP user that solves with full OLL and PLL, along with an efficient cross (which takes 8 moves at maximum) and efficient F2L (which takes almost 30 moves), consists of 55-60 moves, which means that it has a higher move count than Roux and ZZ. However, finger tricks and algorithms are more researched with CFOP than any other method, which explains why the majority of the fastest speedcubers use CFOP as their main speedcubing method.[15]
The CFOP method is the most widely used speed-solving method. It is a more efficient version of the Layer-By-Layer method (also known as the beginner's method). It is very popular due to the vast amount of resources that teach and improve upon the CFOP method. Many top speedcubers, including two-time World Champion Feliks Zemdegs and world record holder Max Park, learn additional sets of algorithms for the last slot and layer, such as Corners of Last Layer (COLL), which orients and permutes the corners when the edges are oriented, or Winter Variation (also known as Valk Last Slot, or VLS), which finishes OLL while inserting the last pair, and ZBLL, which combines the solving processes of OLL corner orientation and PLL in only one algorithm, provided the last-layer edges are oriented.
Pseudoslotting is a technique that allows advanced CFOP solvers to be more creative with efficient solutions. It is an alternative method to F2L, except instead of creating and inserting pairs with matching colors, the bottom layer is intentionally misaligned to allow different pieces to be paired together.[16] This provides more freedom while pairing pieces during F2L. Pseudoslotting is similar to another technique called keyhole in which the bottom layer is misaligned to allow a piece to be inserted independent of its solved counterpart.[17] It is widely believed that Tymon Kolasiński (who holds the European record for a 3x3x3 single with 3.66 seconds)[18][19] is the best speedcuber that utilizes pseudoslotting.[20]
Roux method
The Roux method was invented by French speedcuber Gilles Roux. The first step of the Roux method is to form a 3×2×1 block, usually placed in the lower portion of the left layer. The second step is creating another 3×2×1 on the opposite side, so each block shares a bottom color. The creation of these blocks is commonly known as "block-building".[21] The remaining four corners are then solved using a set of algorithms known as CMLL (Corners of the Last Layer, without regard to the M-slice), which leaves six edges and four centers that are solved in the last step, L6E or LSE (Last Six Edges).
This method is not as dependent on algorithm memorization as the CFOP method since all but the third step is done with intuition as opposed to predefined sets of algorithms. Because of the frequent use of M moves, the Roux method can be performed without any rotations (unlike the CFOP method), which means it is easier to look ahead (solving pieces while at the same time looking for the solution to the next step) while solving. It is also considered one of the most efficient speedsolving methods, with its average move count being between 45 and 50 moves for experienced solvers. However, the Roux method of speedcubing has been criticized over the years because, unlike CFOP, ZZ, or Petrus, Roux requires M (middle layer) slices to solve LSE. Using M slice moves makes it harder to achieve higher TPS (turns per second) because the finger tricks are almost always flicks, but high TPS is achievable through training.
One of the users of this method, Kian Mansour, broke the one-handed (OH) world record average with a time of 9.54 seconds.[22]Sean Patrick Villanueva is the first Roux user to achieve a sub-6 average of five in competition and is ranked tenth in the world by 3x3 average. He also podiumed in 3x3 at the WCA World Championship 2019 (2nd Place).
ZZ method
The ZZ method (short for "Zbigniew Zborowski") is a modern speedcubing method originally proposed by Zbigniew Zborowski in 2006, and built upon since. The method was designed specifically to achieve high turning speeds by focusing on movement ergonomics and is a combination of a block-building method and a layer-by-layer method. The initial pre-planned step is called EOCross and is the most distinctive hallmark of the ZZ method. It involves orienting all edges while placing the cross pieces. It is also common to build an EOLine, mainly used for one-handed solving, where all edges are oriented and only the front and back cross edges are placed. The next step solves the remaining first two layers using only left, right, top, and bottom face turns, one of the advantages of ZZ. On completion of the first two layers, the last layer's edges are all correctly oriented because of edge pre-orientation during EO. The last layer may be completed using a number of techniques, including those used in the CFOP method. An expert variant of this method, ZBLL (Zborowski-Bruchem Last Layer), allows the last layer to be completed in a single step with an average of just over 12 moves but requires a total of 493 algorithms to be learned.[23] Due to the ergonomics of ZZ, rotating when solving will never be needed, unlike in the CFOP method. The ZZ method has fewer moves than CFOP, with ZZ averaging 53.5 compared to CFOP's 55–60 moves. Because ZZ uses EO, it is very move-efficient, these techniques are used in the FMC (Fewest Move Challenge).[24]
Corners-first methods
Corners-first methods involve solving the corners and then finishing the edges with slice turns. Corner-first solutions were common in the 1980s and were one of the most popular methods that 1982 world champion Minh Thai used. Currently, corner-first solutions are rarely used among speedsolvers. Dutch cuber Marc Waterman created a corners-first method in the cube craze and averaged 18 seconds in the mid-late 1980s.
Fewest Moves Challenge (FMC) methods
At the highest level, there is typically not a standard method used for Fewest Moves solving. Rather, competitors attempt to solve the cube intuitively using solving techniques such as blockbuilding, Normal-Inverse-Scramble-Switch (NISS), commutator insertions, and Domino Reduction after its rise to popularity in 2019. Most solves utilize multiple of these techniques in order to generate a solution.
Blindfolded methods
In 2003, when the first blindfolded competitions were organized, world record solvers would use the 3OP (3-Cycle Orientation Permutation) Method, which orients and then permutes pieces using 3 cycles. As of today, methods such as 3-Style and M2 are among the fastest and most popular blind-solving methods. The Old Pochmann Method, which is a method that solves one piece at a time, is a method typically used by beginner blindsolvers. Blindfolded solvers use letter patterns to help memorize sequences of moves in order to solve the cube.
The lettering scheme that blindfolded solvers use is called the Speffz lettering scheme, and each sticker or individual color is given a letter. The way letters are assigned is by starting on the top edge of the top face, going clockwise, and starting with A. The top edge of the top face is A, the right edge is B, the bottom edge is C, and the left edge is D. The same process is done on the other sides in the order top, left, front, right, back, and bottom to get every edge lettered from A to X. The same process is applied to all of the corners, starting with the top left corner and going clockwise in the same face order. A cycle of piece swaps is then used with the letter E being used as a buffer location for corners and D commonly being used for edges in the Old Pochmann method. The current 3x3 average and single blindfolded world record holder is Tommy Cherry, from the United States.[25]
Competitions
Anssi Vanhala solving a 3×3×3 Rubik's Cube with his feet in 36.72 seconds, at the 2009 Estonian Open
Speedcubing competitions have been held every year since 2003. The World Cube Association (WCA) was formed in 2004 to govern all official competitions. For a competition to be official, it must be approved by the WCA and follow the WCA regulations. Included in the regulations is the necessity of having one or more WCA delegate in attendance. A delegate's main role is to ensure all regulations are followed during the competition. Once the competition is finished, results are uploaded to the WCA website. Judges oversee the round. Delegates help the judge. Runners give the scrambled or solved cube to the competitor. A scrambler scrambles the cube.
Format
The majority of puzzle competitions are held using a trimmed mean of five. This involves the competitor executing five solves in the round in question, after which the fastest and slowest solves are disregarded and the mean of the remaining three is used. The 6×6×6 and 7×7×7 events are ranked by a straight mean of three—only three solves, none of which are disregarded. In 3×3×3 blindfolded and 3×3×3 fewest moves challenges, either a straight mean of 3 or the best of 3 is used, while 4×4×4 blindfolded, 5×5×5 blindfolded, and multiple blindfolded challenges are ranked using the best of 1, 2 or 3, depending on the competition.
When a round begins, competitors turn in the puzzle they will use. Puzzles are scrambled using a computer-generated scramble. Each round, five, three, or one (depending on the format mentioned above) scrambles are used. Every competitor in the round will receive each scramble once. Before starting a solution, a competitor has up to 15 seconds to inspect the puzzle (inspection is removed for blindfolded events). This is monitored by a judge with a stopwatch. Once the solution is complete, the judge records the time on the competitor's scorecard, which is signed by both. If the puzzle is unsolved and the timer is stopped, the time is recorded as "DNF" (Did Not Finish). There are also numerous reasons why the solver can receive a two-second addition to the solve time, such as a face being more than 45 degrees off or the competitor going over the allowed inspection time. A competitor can also receive an extra solution to replace the one just completed, for example in the case of a timer malfunction or a duplicate scramble.
The official timer used in competitions is the StackMat Gen 4 or Gen 5 timer, which was originally designed for sport stacking. This device has touch-sensitive pads that are triggered by the user lifting one or both of their hands to start the time and placing both their hands back on the pads after releasing the puzzle to stop the timer.
Only two WCA recognised events are not "speedsolving" events (i.e. are scored by means other than time taken for solves), these being: Fewest Moves Competition, or FMC, which is scored using the amount of moves for a competitor's solution, with a lower number of moves being better, and multiple blindfold solving, or "multi-blind", where a competitor's score is calculated by subtracting the number of unsolved cubes from the number of solved cubes.
Official competitions are currently being held in several categories.
Megaminx, a twelve-sided dodecahedral puzzle solved similarly to a 3x3x3.
Skewb, a cube-shaped puzzle added in 2014 as an official WCA event due to its growing popularity and the ease of its regulations.[26]
Square-1, a cubed puzzle that changes shape as it is solved
Rubik's Clock, a double-sided circle-shaped puzzle with many clocks on it that is considered solved when all clock hands are in the 12 o'clock position.
3x3x3 with Feet (formerly), starting in 2020, 3x3x3 with Feet was removed from the list of official WCA events.[27]
Rubik's Magic (formerly), starting in 2012, Rubik's Magic was removed from the list of official WCA events.
Rubik's Master Magic (formerly), starting in 2012, Rubik's Master Magic was removed from the list of official WCA events.
World Rubik's Cube Championships
The WCA organizes the Rubik's Cube World Championship as the main international competition once every two years. The latest championship was held in Incheon, South Korea from August 12 to 15 August 2023.[28]
The following are the official speedcubing world records approved by the WCA.[43]
Note: For averages of 5 solves, the best time and the worst time are dropped, and the mean of the remaining 3 solves is taken. For events where only 3 solves are done, the mean of all 3 is taken.
A scatter plot of Rubik's Cube world records (single and average) against time. This depicts the improvement made over the years, as well as highlights records that stayed unbroken for an unusual amount of time.
Lubrication
Members of the cubing community lubricate their cubes to allow them to be turned faster, easier, smoother, more controllable, and more reliably than a non-lubricated cube. Silicone-based lubricants are commonly used, applied sparingly to the core, springs, screws, and contact surfaces. Regular maintenance, including cleaning and re-lubrication, ensures optimal performance over time.
The WCA allows lubrication for official competitions.[46]
As a governing body, the WCA has many regulations and guidelines that must be followed by competitors.[47]
The Rubik's Cube is a 3-D combination puzzle invented in 1974 by Hungarian sculptor and professor of architecture Ernő Rubik. Originally called the Magic Cube, the puzzle was licensed by Rubik to be sold by Pentangle Puzzles in the UK in 1978, and then by Ideal Toy Corp in 1980 via businessman Tibor Laczi and Seven Towns founder Tom Kremer. The cube was released internationally in 1980 and became one of the most recognized icons in popular culture. It won the 1980 German Game of the Year special award for Best Puzzle. As of January 2024, around 500 million cubes had been sold worldwide, making it the world's bestselling puzzle game and bestselling toy. The Rubik's Cube was inducted into the US National Toy Hall of Fame in 2014.
The Rubik's Revenge is a 4×4×4 version of the Rubik's Cube. It was released in 1981. Invented by Péter Sebestény, the cube was nearly called the Sebestény Cube until a somewhat last-minute decision changed the puzzle's name to attract fans of the original Rubik's Cube. Unlike the original puzzle, it has no fixed faces: the center faces are free to move to different positions.
The Pocket Cube is a 2×2×2 combination puzzle invented in 1970 by American puzzle designer Larry D. Nichols. The cube consists of 8 pieces, all corners.
Minh Thai is a Vietnamese-American speedcuber. As a sixteen-year-old Eagles Rock High School student from Los Angeles, he won the first world championship on June 5, 1982 in Budapest by solving a Rubik's Cube in 22.95 seconds. He is also the author of the book The Winning Solution (1982), a guide to solving the cube. Later, Ortega Corners-First Solution Method for Rubik's Cube was based on Minh Thai's Winning Solution.
The Professor's Cube is a 5×5×5 version of the original Rubik's Cube. It has qualities in common with both the 3×3×3 Rubik's Cube and the 4×4×4 Rubik's Revenge, and solution strategies for both can be applied.
The Megaminx or Mégaminx is a dodecahedron-shaped puzzle similar to the Rubik's Cube. It has a total of 50 movable pieces to rearrange, compared to the 20 movable pieces of the Rubik's Cube.
Jessica Fridrich is a professor at Binghamton University, who specializes in data hiding applications in digital imagery. She is also known for documenting and popularizing the CFOP method, one of the most commonly used methods for speedsolving the Rubik's Cube, also known as speedcubing. She is considered one of the pioneers of speedcubing, along with Lars Petrus. Nearly all of the fastest speedcubers have based their methods on Fridrich's, usually referred to as CFOP, that is,.
The World Cube Association (WCA) is the worldwide non-profit organization that regulates and holds competitions for mechanical puzzles that are operated by twisting groups of pieces, commonly known as twisty puzzles. The most famous of those puzzles is the Rubik's Cube. Since the start of the WCA there have been over 10,000 competitions. The WCA was founded by Ron van Bruchem of the Netherlands and Tyson Mao of the United States in 2004. The goal of the World Cube Association is to have "more competitions in more countries with more people and more fun, under fair conditions." In 2017, they started work to become a non-profit organization and on November 20, 2017, the state of California accepted the initial registration of the World Cube Association.
Lars Erik Petrus is an accomplished speedcuber. He has been described as a Rubik's Cube icon and master.
The CFOP method, also known as the Fridrich method, is one of the most commonly used methods in speedsolving a 3×3×3 Rubik's Cube and is one of the fastest methods. This method was first developed in the early 1980s, combining innovations by a number of speed cubers. Jessica Fridrich, a Czech speed cuber and the namesake of the method, is generally credited for popularizing it by publishing it online in 1997.
Bob Burton is an American speedcuber, most famous for competing in and organizing competitions all over the world and his former world records on the Rubik's Magic and Rubik's Master Magic.
Ron van Bruchem is a Dutch speedcuber living in Hilversum. He helped create the current resurge of Rubik's Cube enthusiasm by founding the international speedcubing community and organizing international competitions. He is also a founder, delegate and former chairman of the World Cube Association, an organization aiming at the spread of speedcubing as a regulated sport. He is also the host of the website speedcubing.com.
Eric Limeback is a Canadian speedcuber. He is known for his 11/11 3x3x3 multiblindfold Canadian record solve, as well as his standard 3x3x3 blindfolded solving. Limeback was the first Canadian to record a sub-30 second official 3x3x3 blindfolded solve. Limeback began solving the Rubik's Cube in 9th grade. He graduated from Marc Garneau Collegiate Institute in 2010. He formerly held the Guinness World Record for the most 3x3x3 cubes solved in 24 hours, 5800, set from 3–4 October 2013 at Wilfrid Laurier University, Canada.
Feliks Aleksanders Zemdegs is an Australian Rubik's Cube speedsolver. He is one of the only two speedcubers ever to win the World Cube Association World Championship twice, winning in 2013 and 2015, and is widely considered the most successful and greatest speedcuber of all time. He has set more than 350 records across various speedcubing events: 121 world records, 213 continental records, and 7 national records.
Anthony Michael Brooks is an American speed cubing champion. He specializes in the 2x2 cube and classic 3x3 cube, and used to be officially ranked in the top five in the world in both categories as recognized by the World Cube Association. Since learning to solve the cube in March 2008, Brooks has become known for developing advanced speedsolving methods as well as frequently promoting speedcubing in the media. While working as the Liberty Science Center's Speedcuber-in-Residence, Brooks set the Guinness World Record for most Rubik's Cubes solved underwater in a single breath, and also led the team that currently holds the world record for solving the Groovik's Cube, the world's largest functioning Rubik's Cube. In July 2017, Brooks was featured on the debut season of FOX's Superhuman TV show.
Gilles Roux is a French speedcuber primarily known for inventing a 3x3x3 Rubik's Cube method, the Roux Method, and achieving fast times with it.
Mats Valk is a Dutch Rubik's Cube speedsolver. He broke the Rubik's cube single solve world record twice with times of 5.55 seconds in 2013 and 4.74 seconds in 2016. He won the Rubik's Cube European Championship in 2018 and was runner-up for 3x3x3 at the Rubik's Cube World Championships in 2013 and 2015.
The Layer by Layer method, also known as the beginners method, is a method of solving the 3x3x3 Rubik's Cube. Many beginners' methods use this approach, and it also forms the basis of the CFOP speedcubing technique.
Vincent Sheu is an American speedcuber or Rubik's Cube solver from Saratoga, California known for organizing World Cube Association competitions and setting world records in both the Fewest Moves event and the 2x2x2 single solve. He currently serves as a Director and Delegate for the World Cube Association (WCA) and has been an organizer of every annual US Nationals Cubing Competition since 2010. Sheu previously served as the first Chair of the WCA's Regulations Committee with Lucas Garron from 2012 to 2015, directing a complete redrafting of the official competition regulations and guidelines during his tenure. Recently, he has received media attention as the subject of several viral images and video clips at various college sporting events.
Max Park is a Korean- American Rubik's Cube speedsolver, widely considered as one of the greatest cubers of all time. He is the World Champion of 3×3×3 solving and world record holder for the 3x3x3 single solve at 3.13 seconds set on June 11, 2023. Along with Feliks Zemdegs, he is one of only two speedcubers ever to win the World Cube Association World Championship twice, which he did in 2017 and 2023. He is currently tied for 3rd place for the world record average of five 3×3×3 solves at 4.86 seconds, set on February 6, 2023. Park first held this record from April 23, 2017 to June 28, 2017 and was the only cuber other than Feliks Zemdegs to hold the record between September 27, 2009 and June 5, 2021. Park has also set multiple world records in speedsolving in the 4×4×4, 5×5×5, 6×6×6, and 7×7×7 cubes as well as the 3×3×3 One-Handed event. As of September 2, 2023, he has won 479 total events in World Cube Association competitions.
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