Go Player Ratings

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Seki Kotaro

Seki Kotaro (関航太郎) has a rating of 2000, ranked 29 of 452 in professional play. Their highest rating so far is 2160 (March 25, 2024).

Seki Kotaro9 dan関航太郎Nihon Ki-in Tokyo
Rating2000
Rank29
1-year change↓84
Peak rating2160
Last 10230-142
2026 record
10-5
Record since 1927
230-142
Win rate
.618

The rating is calculated from published game results. It does not include any adjustment for playing Black.

Professional ratingsFind a player

Rating history — professional

29 gamesHigh 2096Low 1983
118 gamesHigh 2160Low 1983
181 gamesHigh 2160Low 1983
348 gamesHigh 2160Low 1518

The “All” view starts at 2006; earlier years are used only to warm up the calculation and are not shown.

Recent games

Up to 20 games, newest first. “Change” is the rating movement.
DateOpponent and tournamentResultChange
September 10, 2026Komatsu HidekiGosei Preliminary A　as White↑7
August 27, 2026Hon AkiyoshiJudan Final Preliminary Final　as White↓21
August 24, 2026Hino ShotaHoninbo　Colors unknown↓30
August 20, 2026Watanabe KandaiMeijin Preliminary A Final　as White↑7
August 17, 2026Konishi YoshiakiraKisei League C Round 4　as Black↑6
August 10, 2026Ueno AsamiKisei League C Round 3　as Black↓18
July 23, 2026Murakawa DaisukeTengen Round 4　as Black↓15
July 9, 2026Oya KoichiMeijin　Colors unknown↑1
June 25, 2026Suzuki ShinjiKisei League C Round 2　as Black↑16
June 1, 2026Omote YutoKisei League C Round 1　as Black↑9
May 11, 2026Ryu ShikunTengen Round 3　as White↑9
April 9, 2026Fujisawa RinaTengen Round 2　as Black↑12
February 5, 2026Mutsuura YutaTengen Round 1　as White↑17
January 15, 2026Yamashita KeigoTengen Preliminary A Final　as White↑19
January 8, 2026U BoiHoninbo Final Preliminary Final　as Black↓20
December 11, 2025Motoki KatsuyaOza Preliminary A Final　as Black↓10
December 4, 2025Xiao YuyangTeikei Cup Shun-ei Preliminary　as White↓16
November 27, 2025Hon AkiyoshiJudan Round 2　as Black↓23
November 20, 2025Onishi RyuheiKisei League C Round 5　as Black↓19
November 6, 2025Takeuchi KosukeOza　Colors unknown↑6

Head-to-head

Up to 10 opponents, most-played first. Records are from Seki Kotaro's point of view; jigo and no-result games are not counted as wins or losses. Only games from 1927 onward are included.
OpponentTotalAs BlackAs White
Ichiriki Ryo6-8.4291-54-3
Shibano Toramaru3-9.2501-31-5
Ida Atsushi6-2.7502-12-1
Iyama Yuta0-7.0000-10-5
Sakai Yuki6-1.8572-12-0
Adachi Toshimasa1-5.1671-10-2
Mutsuura Yuta5-1.8332-12-0
Kyo Kagen2-4.3330-21-2
Motoki Katsuya3-2.6002-10-1
Sada Atsushi3-2.6001-12-1
Yu Zhengqi1-4.2001-10-3
Ueno Asami3-2.6001-11-0
Murakawa Daisuke2-3.4001-21-1
Yo Chito3-2.6000-10-0

Record by year

Counted by calendar year, January to December (default wins and losses are included; jigo and no-result games are not). Only games from 1927 onward are counted, so these totals do not match the career records published by the two Ki-in.

YearRecordWin rate
202610-5.667
202524-19.558
202426-24.520
202317-16.515
202223-13.639
202137-15.712
202029-9.763
201918-16.529
201835-17.673
201710-6.625
20161-1.500
20150-1.000
Total230-142.618

Calculated from games played between 1927 and 2026 (as of September 17, 2026).