People · Japan
Kai Harada (原田櫂)
3×3 · top 3.2% of 284,439 all-time · competing since December 2021 · 2021HARA01
Kai Harada (原田櫂) has been competing for 5 years. His best event is the 3×3: a personal-best single of 8.25, set at Tokyo Spring AM 2025, puts him in the top 3.2% of the 284,439 people who have ever been ranked in the event, and 137th in Japan. Until July 2008, no official 3×3 solve in the world had been that fast. Across 20 competitions since December 2021, he has put 154 official solves on the record across three events. Solve to solve, his 3×3 times vary about 14% around a typical one; 65% of the 35,811 competitors with ten or more counted rounds hold a tighter spread. His 3×3 best has come down from 17.81 in December 2021 to 8.25, a 54% improvement. Kai has entered 20 competitions, more competitions than 97% of everyone who has ever competed.
Standing, event by event
vs everyone ever ranked| Event | PB single | PB average | All-time standing | Japan | |
|---|---|---|---|---|---|
| 3×3 | 8.25 | 10.17 | top 3.2% | 137 / 3,329 | |
| 2×2 | 3.81 | 5.32 | top 24.1% | 304 / 1,021 | |
| 5×5 | 1:32.72 | 1:42.82 | top 29.6% | 178 / 420 |
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
- 12 Aug 2023First sub-10 3×3: 8.51 at Rubik's WCA World Championship 2023.
- 30 Jul 2022First sub-15 3×3: 12.90 at Ota Summer 2022.
- 11 Dec 2021First competition: Florida Fall 2021. A 17.81 3×3 single to start from.
Competitions
- Kanto Summer 2026 · 29 Aug 2026
- Japan Championship 2026 · 18 Jul 2026
- Kanto Spring 2026 · 17 May 2026
- Ota Winter 2026 · 25 Jan 2026
- Ota Autumn 2025 · 8 Nov 2025
- Kanto Autumn AM 2025 · 11 Oct 2025
- Kanto Summer AM 2025 · 30 Aug 2025 — 1 personal best set
- Kanto Spring 2025 · 31 May 2025
- Tokyo Spring AM 2025 · 20 Apr 2025 — 1 personal best set
- Tokyo Open AM Winter 2025 · 16 Feb 2025
- Singapore Championship 2025 · 7 Feb 2025 — 1 personal best set
- Shonan PM 2024 · 7 Dec 2024
- Tokai Open PM 2024 · 15 Sep 2024
- Tokyo Challenge VIII 2023 · 4 Nov 2023
- Rubik's WCA World Championship 2023 · 12 Aug 2023 — 1 personal best set
- Tokyo Challenge IV 2023 · 9 Apr 2023 — 1 personal best set
- Tokyo Challenge Winter B 2023 · 12 Feb 2023 — 1 personal best set
- Ota Summer 2022 · 30 Jul 2022 — 1 personal best set
- Florida Spring A 2022 · 12 Mar 2022 — 2 personal bests set
- Florida Fall 2021 · 11 Dec 2021
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.
- Takumi Kawazoe (川添匠) — met in 16 rounds, never finished ahead
- Zirui Wang (王子睿) — met in 14 rounds, finished ahead 9 times
- Shuto Ueno (上野柊斗) — met in 14 rounds, finished ahead twice
Next targets
- A sub-8 3×3 single — 7,931 people have one; it is 0.25 away.
- A sub-3 2×2 single — 26,570 people have one; it is 0.81 away.
Targets move as he improves.