Go Player Ratings

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Hoshikawa Koyo

Hoshikawa Koyo (星川航洋) has a rating of 1555, ranked 227 of 452 in professional play. Their highest rating so far is 1614 (May 19, 2021).

Hoshikawa Koyo4 dan星川航洋Kansai Ki-in
Rating1555
Rank227
1-year change↓36
Peak rating1614
Last 1025-33
2026 record
0-3
Record since 1927
25-33
Win rate
.431

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

Professional ratingsFind a player

Rating history — professional

3 gamesHigh 1582Low 1555
15 gamesHigh 1604Low 1546
21 gamesHigh 1605Low 1546
58 gamesHigh 1614Low 1473

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 9, 2026Nishi TakenobuHoninbo Preliminary B　as Black↓6
September 2, 2026Yahata NaokiOza Preliminary B　as Black↓20
February 11, 2026Kiyonari TetsuyaKisei First Tournament Preliminary Round 2　Colors unknown↓10
August 27, 2025Tanaka KoyuGosei Preliminary A　as Black↓5
April 16, 2025Fujita ReoGosei Preliminary B　as Black↑12
April 10, 2025Nakahama KonosukeKisei First Tournament Preliminary Semifinal　Colors unknown↓20
March 5, 2025Sakakibara MasateruKisei First Tournament Preliminary Quarterfinal　Colors unknown↑9
January 30, 2025Ikemoto RyotaKisei First Tournament Preliminary Round 2　Colors unknown↑23
November 13, 2024Francis MeyerTengen Preliminary A　as Black↑11
May 15, 2024Kiyonari TetsuyaJudan Preliminary A　as White↓8
April 10, 2024Sato YutaKisei First Tournament Round 4　as Black↓14
March 13, 2024Yokota ShigeakiKisei First Tournament Preliminary Quarterfinal　Colors unknown↑19
February 22, 2024Sakuramoto AyakoKisei First Tournament Preliminary Round 2　Colors unknown↑8
December 20, 2023Fujiwara KatsuyaKisei First Tournament Preliminary Round 1　Colors unknown↑10
November 29, 2023Watanabe KokiTengen Preliminary A　as White↓12
August 21, 2023Fujii NaokiKansai Ki-in First Place Tournament Preliminary　as Black↑7
March 15, 2023Nishimura JinMeijin Preliminary C　as White↓19
December 21, 2022Hasegawa SunaoKisei First Tournament Preliminary Round 1　Colors unknown↓17
March 2, 2022Inoue NaokiKisei First Tournament Preliminary Quarterfinal　Colors unknown↓18
January 13, 2022Kim PyonminKisei First Tournament Preliminary Round 2　Colors unknown↑13

Head-to-head

Up to 10 opponents, most-played first. Records are from Hoshikawa Koyo'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
Onoda Takuya2-01.0000-00-0
Aragaki Shun2-01.0000-02-0
Kumamoto Shusei0-2.0000-00-0
Murakawa Daisuke1-1.5001-00-1
Sato Yuta0-2.0000-10-1
Sakakibara Masateru2-01.0000-00-0
Yuki Satoshi1-1.5001-00-1
Kiyonari Tetsuya0-2.0000-00-1
Cho Chien0-1.0000-00-1
Oyama Kunio1-01.0000-00-0

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
20260-3.000
20253-2.600
20243-2.600
20232-2.500
20221-2.333
20213-4.429
20202-01.000
20190-2.000
20182-3.400
20172-2.500
20163-3.500
20152-2.500
20130-3.000
20122-1.667
20110-1.000
20070-1.000
Total25-33.431

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