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People → Japan → Katsunori Ishiguro (石黒克典)

People · Japan

Katsunori Ishiguro (石黒克典)

3×3 · top 4.1% of 284,439 all-time · competing since April 2014 · 2014ISHI02

Katsunori Ishiguro (石黒克典) has been competing for 12 years. His best event is the 3×3: a personal-best single of 8.65, set at Japan Championship 2019, puts him in the top 4.1% of the 284,439 people who have ever been ranked in the event, and 172nd in Japan. Until July 2008, no official 3×3 solve in the world had been that fast. Across 37 competitions since April 2014, he has put 693 official solves on the record across eight events. Solve to solve, his 3×3 times vary about 11% around a typical one, steadier than 85% of the 35,811 competitors with ten or more counted rounds. His 3×3 best has come down from 18.03 in April 2014 to 8.65, a 52% improvement. Katsunori has entered 37 competitions, more competitions than 99% of everyone who has ever competed.

3×3
best event — top 4.1% of 284,439 all-time
8.65
signature single · Japan Championship 2019
693
official solves on the record
11%
solve-to-solve spread · steadier than 85% of the field

Standing, event by event

vs everyone ever ranked
EventPB singlePB averageAll-time standingJapan
3×38.6510.17
top 4.1%172 / 3,329
2×22.144.97
top 5.7%70 / 1,021
4×439.2247.55
top 11.2%112 / 667
5×51:09.491:14.18
top 11.3%69 / 420
3×3 one-handed26.0529.44
top 37.0%293 / 529
Megaminx1:54.392:15.74
top 42.8%209 / 313
7×75:03.655:41.20
top 51.7%106 / 188
3×3 Fewest Moves45 moves—
early days — 2 solves155 / 201

Percentile against all competitors ever ranked in each event, a fairer measure than raw rank, because the pools differ by a factor of ten.

The line so far

Japan Contest Spring 2014: 18.03Kawasaki Spring 2014: 17.22Japan Contest Autumn 2014: 13.27Asian Championship 2014: 12.91UT Open 2014: 12.71Tokyo Pyraminx Open 2015: 12.33Kawasaki Spring 2016: 9.38Cube Camp in Kanazawa 2016: 10.40Tachikawa Open 2016: 12.40JRCA Kansai Fall 2016: 10.44Japan Open 2016: 10.23Tribox Open Winter 2017: 12.20Circles Open Spring 2017: 8.73Kansai Open 2017: 11.13Tohoku Open 2017: 9.74Meguro 2017: 9.96World Rubik's Cube Championship 2017: 9.68Cube Camp in Kanazawa 2017: 11.07Yokohama 2017: 10.49Suginami Open 2017: 8.84Kansai Big Cube 2017: 10.27Japan Open 2017: 10.83Kobe Open 2018: 10.11YRCC Open 2018: 9.23Kansai Open 2018: 9.33Tribox Open Spring 2018: 10.86Omiya Bigs 2018: 10.34Cube Camp in Kanazawa 2018: 10.49WCA Asian Championship 2018: 9.63Japan Championship 2018: 12.19Tribox Open Spring 2019: 10.16Reiwa Anniversary 2019: 11.16Tokai Open 2019: 9.53WCA World Championship 2019: 9.00Kurukuru Summer 2019: 10.52Japan Championship 2019: 8.658.6518.0329 Apr 20142 Nov 2019

Best single per competition, 3×3. Faster is higher — the axis is the right way up.

The story so far

Competitions

Reading this page: a single is one solve's time · an average is the middle three of five solves, best and worst discarded · a PB is a personal best · a DNF (did not finish) is an attempt with no valid result: a popped piece, an unsolved face, an over-limit memorisation · top X% compares against everyone ever ranked in that event, which is fairer than raw rank because event pools differ tenfold.

The circuit

The people whose scorecards keep turning up next to his.

Next targets

  • A sub-8 3×3 single — 7,931 people have one; it is 0.65 away.
  • A sub-2 2×2 single — 8,848 people have one; it is 0.14 away.

Targets move as he improves.