Kato Masao

Kato Masao (加藤正夫) has a rating of 1770.

Retired. The rating shown is the rating at retirement.

Kato Masao加藤正夫Nihon Ki-inAlso known as: 加藤剱正

Rating1770

Rank—

1-year change—

Peak rating—

Last 101048-623(6 by default, 1 lost by default)

2005 record: 0-4
Record since 1927: 1048-623(2 no result)
Win rate: .627

Rating at retirement (not included in the rating list)

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

Professional ratings Find a player

Recent games

Up to 20 games, newest first. “Change” is the rating movement.
Date	Opponent and tournament	Result	Change
March 10, 2005	Imamura ToshiyaTengen Main Tournament Round 2　Colors unknown	Loss	↓12
February 17, 2005	O RisseiGosei Main Tournament Round 2　Colors unknown	Loss	↓17
January 30, 2005	Cho UNHK Cup Main Tournament Round 3　Colors unknown	Loss	↓7
January 27, 2005	Mimura TomoyasuOza Final Preliminary Round 1　Colors unknown	Loss	↓14
December 16, 2004	Komatsu HidekiKisei　Colors unknown	Loss	↓16
December 2, 2004	Yuki SatoshiTengen Round 1　as Black	Win	↑23
November 28, 2004	Yokota ShigeakiNHK Cup Main Tournament Round 2　Colors unknown	Win	↑9
November 18, 2004	Goto ShungoGosei Round 1　as Black	Win	↑13
October 21, 2004	Kono TakashiGosei　Colors unknown	Win	↑12
September 2, 2004	Komatsu HidekiGosei　Colors unknown	Win	↑21
August 19, 2004	Yamashita KeigoTengen Round 4　as Black	Loss	↓8
August 12, 2004	Kono RinMeijin　Colors unknown	Loss	↓11
August 6, 2004	Kamimura HaruoRyusei Championship Tournament Round 1　Colors unknown	Loss	↓18
July 22, 2004	Yamashita KeigoJudan Losers' Section Round 1　as Black	Loss	↓9
July 19, 2004	Yamashita KeigoAgon Kiriyama Cup Main Tournament Round 1　Colors unknown	Loss	↓10
July 15, 2004	Kataoka SatoshiTengen Round 3　as White	Win	↑17
July 8, 2004	Takao ShinjiHoninbo Final Preliminary Semifinal　Colors unknown	Loss	↓7
June 17, 2004	Rin KaihoHoninbo Final Preliminary　Colors unknown	Win	↑17
June 10, 2004	Ryu ShikunNEC Cup Round 1　as White	Loss	↓15
June 3, 2004	Fukui SusumuMeijin　Colors unknown	Win	↑7

Head-to-head

Up to 10 opponents, most-played first. Records are from Kato Masao's point of view; jigo and no-result games are not counted as wins or losses. Only games from 1927 onward are included.
Opponent	Total	As Black	As White
Cho Chikun	44-70.386	18-34	25-36
Rin Kaiho	59-55.517	30-30	28-25
Kobayashi Koichi	60-51.540	34-28	26-23
Otake Hideo	40-50.444	19-21	21-29
Takemiya Masaki	41-32.562	25-12	14-20
Sakata Eio	27-22.551	17-5	10-17
Fujisawa Shuko	33-14.702	19-7	14-7
Ishida Yoshio	30-11.732	19-6	11-5
O Rissei	21-18.538	8-11	13-6
Kataoka Satoshi	28-9.757	15-2	13-7
Yoda Norimoto	16-20.444	6-9	10-11
Hane Yasumasa	22-12.647	10-4	12-8
Yamashiro Hiroshi	18-10.643	10-2	8-8
O Meien	16-11.593	10-6	6-5
Hashimoto Shoji	14-10.583	5-8	9-2
Ohira Shuzo	13-7.650	5-3	8-4
Kudo Norio	14-5.737	7-1	6-4
Awaji Shuzo	14-5.737	11-1	3-4
Honda Kunihisa	16-3.842	10-0	6-3
Kobayashi Satoru	12-7.632	3-2	9-5
Takagi Shoichi	13-6.684	8-1	5-5
Ryu Shikun	8-10.444	3-4	5-6
Hikosaka Naoto	9-8.529	5-4	4-4
Hashimoto Utaro	10-6.625	7-1	3-5
Cho U	6-9.400	2-3	3-5
Komatsu Hideki	10-4.714	4-1	5-2
Ishida Akira	9-5.643	5-3	4-1
Shimamura Toshihiro	9-5.643	5-2	4-3
Fujisawa Hosai	11-2.846	8-0	3-2
Yamabe Toshiro	11-1.917	6-0	5-1
Tono Hiroaki	9-3.750	6-0	3-3
Kojima Takaho	9-2.818	6-2	3-0
Yamada Kimio	6-5.545	3-3	3-1
Chino Tadahiko	9-1.900	8-0	1-1
Ishii Kunio	7-3.700	3-2	4-1
Sugiuchi Masao	7-3.700	5-2	2-1
Takagawa Shukaku	5-5.500	2-2	3-3
Magari Reiki	7-2.778	3-1	4-1
Tozawa Akinobu	8-1.889	3-0	5-1
Shiraishi Yutaka	9-01.000	1-0	8-0
Takao Shinji	3-6.333	2-1	1-2
Miyazawa Goro	6-3.667	3-1	3-2
Cho Sonjin	7-2.778	5-0	2-2
Hane Naoki	5-3.625	3-2	1-1
Imamura Toshiya	6-2.750	4-0	2-1
Iwata Tatsuaki	5-3.625	2-1	3-2
Yo Kagen	7-1.875	5-1	2-0
Ishigure Ikuro	7-1.875	5-1	2-0
Yuki Satoshi	5-3.625	2-1	3-2
Mimura Tomoyasu	4-3.571	4-0	0-2
Kajiwara Takeo	4-3.571	2-1	2-2
Sakakibara Shoji	6-1.857	3-0	3-1
Yamashita Keigo	0-7.000	0-4	0-1
Oyama Kunio	5-1.833	3-0	2-1
Sonoda Yuichi	5-1.833	0-1	5-0
Naganuma Makoto	5-1.833	3-1	2-0
Yokota Shigeaki	4-2.667	1-2	2-0
Haruyama Isamu	6-01.000	4-0	2-0
Nakamura Hidehito	6-01.000	3-0	3-0
Kamimura Haruo	3-3.500	1-0	2-1
Sakai Takeshi	6-01.000	4-0	2-0
Kano Yoshinori	5-01.000	2-0	3-0
Oya Koichi	4-1.800	2-0	2-1
Kamimura Kunio	4-1.800	3-0	1-1
Sanno Hirotaka	4-1.800	2-1	2-0
Kada Katsuji	3-2.600	2-0	1-2
Miyashita Shuyo	4-1.800	3-0	1-1
Ishii Mamoru	5-01.000	1-0	4-0

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.

Year	Record	Win rate
2005	0-4	.000
2004	12-18	.400
2003	17-21	.447
2002	29-20	.592
2001	21-13	.618
2000	14-14	.500
1999	23-16	.590
1998	23-22	.511
1997	32-22	.593
1996	23-12	.657
1995	40-25	.615
1994	43-15	.741
1993	44-24	.647
1992	36-9	.800
1991	31-21	.596
1990	26-18	.591
1989	22-26	.458
1988	27-26	.509
1987	37-16	.698
1986	38-13	.745
1985	33-17	.660
1984	33-19	.635
1983	28-14	.667
1982	26-19	.578
1981	29-25	.537
1980	24-15	.615
1979	31-11	.738
1978	30-20	.600
1977	26-10	.722
1976	37-13	.740
1975	22-11(2 no result)	.667
1974	30-17	.638
1973	31-9	.775
1972	22-12	.647
1971	28-14	.667
1970	22-11	.667
1969	21-9	.700
1968	14-8	.636
1967	13-6	.684
1966	6-4	.600
1965	3-3	.500
1964	1-1	.500
Total	1048-623(2 no result)	.627

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