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People → Japan → Sayuri Koba (古場小百合)

People · Japan

Sayuri Koba (古場小百合)

3×3 · top 9.5% of 284,439 all-time · competing since October 2008 · 2008KOBA02

Sayuri Koba (古場小百合) has been competing for 18 years. Her best event is the 3×3: a personal-best single of 10.68, set at Asian Championship 2014, puts her in the top 9.5% of the 284,439 people who have ever been ranked in the event, and 417th in Japan. Until August 2006, no official 3×3 solve in the world had been that fast. Across 12 competitions since October 2008, she has put 107 official solves on the record across four events. Solve to solve, her 3×3 times vary about 11% around a typical one, steadier than 81% of the 35,811 competitors with ten or more counted rounds. Her 3×3 best has come down from 30.94 in October 2008 to 10.68, a 65% improvement. Sayuri has entered twelve competitions, more competitions than 94% of everyone who has ever competed.

3×3
best event — top 9.5% of 284,439 all-time
10.68
signature single · Asian Championship 2014
107
official solves on the record
11%
solve-to-solve spread · steadier than 81% of the field

Standing, event by event

vs everyone ever ranked
EventPB singlePB averageAll-time standingJapan
3×310.6813.09
top 9.5%417 / 3,329
3×3 one-handed20.1222.17
top 20.8%174 / 529
2×27.007.68
top 60.4%715 / 1,021
4×41:28.031:40.05
top 62.1%530 / 667

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 Open 2008: 30.94Toyama Open 2009: 17.83Kawasaki Open 2010: 12.4130th Anniversary MegaHouse Cup 2010: 13.66UT Open 2011: 12.75Asian Championship 2014: 10.68Kawasaki Spring 2016: 12.77Kanto Summer 2016: 12.13Japan Open 2016: 12.13Tokyo Challenge VIII 2023: 13.3310.6830.944 Oct 20084 Nov 2023

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 her.

Next targets

  • A sub-10 3×3 single — 21,172 people have one; it is 0.68 away.
  • A sub-20 3×3 one-handed single — 15,081 people have one; it is 0.12 away.

Targets move as she improves.