People · Japan
Kotaro Sumi (角浩太郎)
Pyraminx · top 41.5% of 129,321 all-time · competing since September 2023 · 2023SUMI03
Kotaro Sumi (角浩太郎) has been competing for 3 years. His best event is the Pyraminx: a personal-best single of 8.61, set at Katano Summer 2025, puts him in the top 41.5% of the 129,321 people who have ever been ranked in the event, and 396th in Japan. Across 5 competitions since September 2023, he has put 54 official solves on the record across four events. Solve to solve, his 3×3 times vary about 12% around a typical one, an early reading from 5 counted rounds. His 3×3 best has come down from 38.01 in September 2023 to 23.19, a 39% improvement. Kotaro has entered five competitions, more competitions than 83% of everyone who has ever competed.
Standing, event by event
vs everyone ever ranked| Event | PB single | PB average | All-time standing | Japan | |
|---|---|---|---|---|---|
| Pyraminx | 8.61 | 19.56 | top 41.5% | 396 / 688 | |
| 3×3 | 23.19 | 29.32 | top 48.4% | 1,742 / 3,329 | |
| Skewb | 11.83 | 16.24 | top 65.2% | 278 / 338 | |
| Clock | 30.44 | 39.95 | top 84.9% | 247 / 263 |
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
Best single per competition, 3×3. Faster is higher — the axis is the right way up.
The story so far
- 15 Sep 2025Three personal bests in one day at Katano Summer 2025.
- 15 Jun 2025First sub-30 3×3: 27.33 at Kansai Odd and BLD 2025.
- 9 Sep 2023First competition: Tokai Open 2023. A 38.01 3×3 single to start from.
Competitions
- Katano Summer 2025 · 15 Sep 2025 — 3 personal bests set
- Kansai Odd and BLD 2025 · 15 Jun 2025 — 1 personal best set
- Tokai Spring 2025 · 12 Apr 2025 — 1 personal best set
- Hiroshima Winter 2024 · 10 Feb 2024 — 1 personal best set
- Tokai Open 2023 · 9 Sep 2023
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.
- Kohdai Kusatani (草谷幸大) — met in 12 rounds, never finished ahead
- Kantaro Sakamoto (坂本貫太郎) — met in 12 rounds, never finished ahead
- Hajime Miyazaki (宮崎朔) — met in 11 rounds, finished ahead once
Next targets
- A sub-8 Pyraminx single — 46,752 people have one; it is 0.61 away.
- A sub-20 3×3 single — 113,584 people have one; it is 3.19 away.
Targets move as he improves.