People · Republic of Korea
Hajin Jeon (전하진)
2×2 · top 1.3% of 186,767 all-time · competing since January 2018 · 2018JEON01
Hajin Jeon (전하진) has been competing for 9 years. His best event is the 2×2: a personal-best single of 1.28, set at Cube Camp in Jeju 2026, puts him in the top 1.3% of the 186,767 people who have ever been ranked in the event, and 31st in Republic of Korea. Until November 2008, no official 2×2 solve in the world had been that fast. Across 10 competitions since January 2018, he has put 411 official solves on the record across 13 events. Solve to solve, his 3×3 times vary about 12% around a typical one, steadier than 67% of the 35,811 competitors with ten or more counted rounds. His 3×3 best has come down from 25.65 in January 2018 to 7.31, a 72% improvement. Hajin has entered ten competitions, more competitions than 92% of everyone who has ever competed.
Standing, event by event
vs everyone ever ranked| Event | PB single | PB average | All-time standing | Republic of Korea | |
|---|---|---|---|---|---|
| 2×2 | 1.28 | 1.94 | top 1.3% | 31 / 2,319 | |
| Pyraminx | 2.18 | 4.91 | top 1.5% | 32 / 1,271 | |
| 3×3 | 7.31 | 8.44 | top 1.7% | 104 / 4,352 | |
| 4×4 | 32.71 | 36.21 | top 4.7% | 98 / 1,308 | |
| 5×5 | 1:00.19 | 1:10.12 | top 5.6% | 62 / 716 | |
| Skewb | 3.28 | 4.76 | top 6.5% | 67 / 854 | |
| 3×3 one-handed | 15.08 | 19.53 | top 8.3% | 115 / 966 | |
| 6×6 | 2:09.97 | 2:19.83 | top 15.3% | 73 / 329 | |
| Megaminx | 1:10.15 | 1:17.76 | top 15.7% | 110 / 524 | |
| Clock | 8.55 | 10.08 | top 17.7% | 124 / 536 | |
| Square-1 | 15.84 | 21.66 | top 18.3% | 78 / 371 | |
| 3×3 blindfolded | 1:39.18 | 1:53.36 | top 26.3% | 69 / 217 | |
| 7×7 | 3:58.80 | 4:00.48 | top 30.2% | 105 / 254 |
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
- 21 Feb 2026Five personal bests in one day at Cube Camp in Jeju 2026.
- 15 Aug 2025Twelve personal bests in one day at Korea Open 2025.
- 26 Oct 2024Three personal bests in one day at Daegu Autumn 2024.
- 3 Feb 2024Four personal bests in one day at Daegu Cold Winter 2024.
- 12 Aug 2023First sub-10 3×3: 9.78 at Rubik's WCA World Championship 2023.
- 12 Aug 2023Five personal bests in one day at Rubik's WCA World Championship 2023.
Competitions
- Cube Camp in Jeju 2026 · 21 Feb 2026 — 5 personal bests set
- Korean Championship 2025 · 27 Dec 2025 — 2 personal bests set
- Korea Open 2025 · 15 Aug 2025 — 12 personal bests set
- Daegu Autumn 2024 · 26 Oct 2024 — 3 personal bests set
- Daegu Cold Winter 2024 · 3 Feb 2024 — 4 personal bests set
- Rubik's WCA World Championship 2023 · 12 Aug 2023 — 5 personal bests set
- Daegu Hot Spring 2023 · 15 Apr 2023 — 5 personal bests set
- Korean Championship 2019 · 16 Aug 2019 — 5 personal bests set
- CWR Fall 2018 · 29 Sep 2018 — 3 personal bests set
- Cubedu Korea 2018 · 26 Jan 2018
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.
- DongSoo Park (박동수) — met in 83 rounds, finished ahead 5 times
- Ko Youngjin (고영진) — met in 79 rounds, finished ahead 43 times
- Minseo Gu (구민서) — met in 72 rounds, finished ahead 23 times
Next targets
- A sub-1 2×2 single — 1,032 people have one; it is 0.28 away.
- A sub-2 Pyraminx single — 1,476 people have one; it is 0.18 away.
Targets move as he improves.