34th iChess Cup

Open SwissStandard

62 players participated in this 6-round tournament, held from 07 Sept 2025 to 14 Sept 2025 in Seoul, South Korea. 2 federations represented. Top 10 Elo average was 1670, and top seed was Jaehyun Sung (🇰🇷 KOR, 1778).

Eram Joo (🇰🇷 KOR, 1569) won with 5.5/6, ahead of Jaemin Bae (5.0) and Haseong Son (5.0). Joo shared the lead from round 4 and won solo starting round 5.

The biggest upset came in round 2: Sihwan Choi (1516) beat Junhyeon Chung (1763), a +247-point gap.

Location

🇰🇷Seoul, South Korea

Dates

07 Sept 2025 → 14 Sept 2025

Time control

Standard: 60 minutes for game

System

Swiss · 6 rounds

Top seed

🇰🇷Jaehyun Sung1778

Avg top 10

1,670

Participants

Federations · 2 represented

🇰🇷South Korea×54

🇬🇺Guam×1

Top 3

🥇
Eram Joo
🇰🇷KOR·1569
5.5pts·1919perf+75.2
🥈
Jaemin Bae
🇰🇷KOR·1640
5.0pts·1755perf+27.6
🥉
Haseong Son
🇰🇷KOR·1426
5.0pts·1818perf+100.0

How it unfolded

Top 6 · 6 rounds

Eram Joo led from R5; +0.5-point edge over the runner-up. Title race converged from 3 co-leaders at R4 to 1 by R5.

Co-leaders

Joo5.5Son5Kim5Bae5Oh5Kang4

R5–R6 · LEAD HELD

Eram Joo held the sole lead from R5 through R6 without losing it.

R5 · HEAD-TO-HEAD · WINNER VS 2ND

Eram Joo beat Haseong Son (Black).

WIN STREAKS · 3 top finishers

Eram Joo 5 wins (R1–R5)Haseong Son 4 wins (R1–R4)Hajoon Kim 4 wins (R1–R4)

Key matchups · top 4

Head-to-head between the four finishers

Player	1	2	3	4
1Eram Joo	*	1	½	—
2Haseong Son	0	*	—	1
3Hajoon Kim	½	—	*	—
4Jaemin Bae	—	0	—	*

Grille américaine

#	Player	Elo	Fed	R1	R2	R3	R4	R5	R6	Pts	Bu C1	Bu	SB	Perf	Δ
1	Joo, Eram	1569	KOR	+48N	+18B	+6N	+16B	+3N	=4B	5.5	20.5	21.5	19.00	1919	+75.2
2	Bae, Jaemin	1640	KOR	+8N	+12B	+14N	−3B	+20N	+7B	5.0	20.5	23.5	18.50	1755	+27.6
3	Son, Haseong	1426	KOR	+49N	+7B	+33N	+2N	−1B	+14B	5.0	20.5	21.5	16.00	1818	+100.0
4	Kim, Hajoon	1693	KOR	+35N	+36B	+19N	+20B	=11N	=1N	5.0	18.0	20.0	15.25	1764	+14.0
5	Oh, Jaemin	1575	KOR	+52N	+17B	−29N	+18B	+8N	+6B	5.0	17.5	18.5	15.50	1781	+37.2
6	Shin, Yisoo	1702	KOR	+41B	+22N	−1B	+15N	+10B	−5N	4.0	21.0	23.0	12.50	1604	-22.4
7	Kim, Sunyong	1606	KOR	+10B	−3N	+31B	+21N	+22B	−2N	4.0	20.0	22.5	12.50	1385	-24.4
8	Baek, Isu	0	KOR	−2B	+50N	+32B	+13N	−5B	+22N	4.0	19.5	20.5	10.50	1560	0.0
9	Kang, Hah	0	KOR	−19N	+26B	+25N	=14B	+36N	=11B	4.0	16.5	18.5	11.75	1651	+7.6
10	Cho, Minje	0	KOR	−7N	+49B	+36N	+19B	−6N	+24B	4.0	16.0	17.0	9.00	1582	0.0
11	Kim, Jio	1511	KOR	−31B	+42N	+40B	+37N	=4B	=9N	4.0	15.5	17.5	10.50	1663	+21.6
12	An, Seunggi	1457	KOR	+50B	−2N	−21B	+39N	+40B	+37N	4.0	14.0	15.0	7.00	1524	+7.2
13	Lee, Yoonsoo	1457	KOR	+61N	−44B	+48N	−8B	+23N	+18B	4.0	13.0	13.0	7.00	1540	+8.4
14	Choi, Jungwoon	1538	KOR	+53N	+55B	−2B	=9N	+31B	−3N	3.5	17.5	18.5	6.50	1291	-47.6
15	Lee, Chanjoo	1591	KOR	+34N	+25B	=16N	−6B	=24N	=17B	3.5	17.0	19.5	10.50	1528	-15.2
16	Choi, Sihwan	1516	KOR	+38B	+45N	=15B	−1N	−28B	+32N	3.5	16.5	18.5	8.25	1654	+45.6
17	Lee, Juwon A	1440	KOR	+62B	−5N	+38B	−22N	+21B	=15N	3.5	16.5	16.5	6.75	1432	-6.0
18	Kim, Hyunwoo B	1425	KOR	+37B	−1N	+39B	−5N	+27B	−13N	3.0	19.5	21.5	7.00	1327	-19.2
19	Lee, Jinwoo	1574	KOR	+9B	+21N	−4B	−10N	+41B	−28N	3.0	19.0	21.0	9.00	1614	+6.4
20	Kwon, Raein	1563	KOR	F	+23B	+44N	−4N	−2B	+25B	3.0	18.0	18.0	8.00	1611	+14.8
21	Choi, Jaein	0	KOR	+26N	−19B	+12N	−7B	−17N	+36B	3.0	17.5	19.5	9.00	1514	0.0
22	Kim, Moonso	1466	KOR	+60N	−6B	+52N	+17B	−7N	−8B	3.0	16.5	16.5	4.50	1438	-2.6
23	Kim, Hanjun A	0	KOR	+32B	−20N	+27B	−28N	−13B	+41N	3.0	15.5	17.5	7.50	1521	0.0
24	Kim, Taeu	1515	KOR	+46N	−29B	=34N	+33B	=15B	−10N	3.0	15.5	17.0	7.00	1675	+31.6
25	Shin, Seojun	1457	KOR	+43B	−15N	−9B	+49N	+38B	−20N	3.0	14.5	15.5	5.00	1352	-20.4
26	Chung, Jaeheon	1580	KOR	−21B	−9N	+50B	−40N	+43B	+31N	3.0	13.5	14.5	5.50	1519	-3.2
27	Shin, Yijoon	1444	KOR	−39N	+53B	−23N	+48B	−18N	+49B	3.0	10.0	11.0	3.00	624	-21.6
28	Li, Artem Serg	1693	KOR	F	F	F	+23B	+16N	+19B	3.0	9.5	9.5	9.50	2350	+25.2
29	Sung, Jaehyun	1778	KOR	+47B	+24N	+5B	F	F	F	3.0	9.5	9.5	9.50	2361	+9.2
30	Park, Sihun	1463	KOR	F	F	F	+60B	+34N	+38N	3.0	4.5	4.5	4.50	2225	+18.0
31	Lim, Seonghyeon	0	KOR	+11N	=33B	−7N	+34B	−14N	−26B	2.5	17.0	19.5	7.75	1394	0.0
32	Son, Joohyuk	1551	KOR	−23N	+39B	−8N	=35B	+33N	−16B	2.5	15.5	17.5	5.75	1526	-2.8
33	Chung, Inho	1541	KOR	+42B	=31N	−3B	−24N	−32B	+46N	2.5	15.0	16.5	4.75	1287	-52.0
34	Cho, Yunki	0	KOR	−15B	+43N	=24B	−31N	−30B	+42N	2.5	14.0	16.0	5.50	1249	0.0
35	Kim, Yeonseo	0	KOR	−4B	+51N	−45B	=32N	−37B	+57N	2.5	12.5	13.5	3.25	1527	0.0
36	Jeon, Sehyun	1472	KOR	+51B	−4N	−10B	+42N	−9B	−21N	2.0	18.0	19.0	3.00	863	-20.0
37	Yun, Yejoon	0	KOR	−18N	F	+41B	−11B	+35N	−12B	2.0	15.5	15.5	4.50	1249	0.0
38	Lee, Seoha	0	KOR	−16N	+54B	−17N	+46B	−25N	−30B	2.0	14.5	15.5	2.50	1328	-31.2
39	Shin, Seojun A	0	KOR	+27B	−32N	−18N	−12B	−?N	+56B	2.0	13.5	13.5	4.00	1233	0.0
40	An, Teaha	0	KOR	−44N	+61B	−11N	+26B	−12N	−?B	2.0	13.0	13.0	3.00	1286	0.0
41	Park, Seojin A	1406	KOR	−6N	+60B	−37N	+51B	−19N	−23B	2.0	13.0	13.0	1.00	841	-19.2
42	Kim, Howon	0	KOR	−33N	−11B	+60N	−36B	+51N	−34B	2.0	12.0	12.0	1.00	686	0.0
43	Seo, Sarang	0	KOR	−25N	−34B	−54N	+56B	−26N	+48B	2.0	10.5	11.5	2.00	680	0.0
44	Kim, Junesun	1652	GUM	+40B	+13N	−20B	F	F	F	2.0	9.0	9.0	6.00	1500	-16.4
45	Chung, Junhyeon	1763	KOR	+54N	−16B	+35N	F	F	F	2.0	7.0	7.0	3.50	1462	-28.4
46	Lim, Chanhee	0	KOR	−24B	=47N	−58B	−38N	+48N	−33B	1.5	10.0	11.0	1.75	693	-64.8
47	Cho, Jungbin	1419	KOR	−29N	=46B	+55N	F	F	F	1.5	5.5	5.5	1.75	1406	0.0
48	FIDE 13236148	0	—	−1B	+58N	−13B	−27N	−46B	−43N	1.0	16.0	17.0	1.00	1239	0.0
49	Suh, Hannah	0	KOR	−3B	−10N	F	−25B	+57N	−27N	1.0	16.0	16.0	1.00	1251	0.0
50	Park, Sejin A	0	KOR	−12N	−8B	−26N	−57B	−56N	+60B	1.0	13.0	13.0	0.00	692	-47.2
51	FIDE 13216848	0	—	−36N	−35B	F	−41N	−42B	+59N	1.0	9.5	9.5	1.00	655	0.0
52	FIDE 13234943	0	—	−5B	+62N	−22B	F	F	F	1.0	8.0	8.0	0.00	734	0.0
53	FIDE 13235834	0	—	−14B	−27N	+62B	F	F	F	1.0	6.5	6.5	0.00	732	0.0
54	Baik, Junyoung	1407	KOR	−45B	−38N	+43B	F	F	F	1.0	6.0	6.0	2.00	795	-11.4
55	Moon, Changjun	0	KOR	+58B	−14N	−47B	F	F	F	1.0	6.0	6.0	1.00	1553	0.0
56	Kutbidinov, Aydar	0	KOR	F	F	F	−43N	+50B	−39N	1.0	5.0	5.0	1.00	1432	0.0
57	Jang, Seyong	1430	KOR	F	F	F	+50N	−49B	−35B	1.0	4.5	4.5	1.00	2212	+18.4
58	Kwak, Yeseong	1493	KOR	−55N	−48B	+46N	F	F	F	1.0	3.5	3.5	1.50	2223	+16.0
59	FIDE 13234935	0	—	F	F	F	−?B	+60N	−51B	1.0	1.0	1.0	0.00	688	0.0
60	FIDE 13231049	0	—	−22B	−41N	−42B	−30N	−59B	−50N	0.0	11.0	12.0	0.00	645	0.0
61	Ryu, Dowoon	0	KOR	−13B	−40N	F	F	F	F	0.0	7.0	7.0	0.00	657	0.0
62	FIDE 13236156	0	—	−17N	−52B	−53N	F	F	F	0.0	5.5	5.5	0.00	655	0.0

Key insights

Biggest movers and upsets — the story behind the numbers.

Top rating gainers

1Son, HaseongKOR
+100.0
5.0 pts · #2
2Joo, EramKOR
+75.2
5.5 pts · #1
3Choi, SihwanKOR
+45.6
3.5 pts · #7

Top rating losers

1Lim, ChanheeKOR
-64.8
1.5 pts · #53
2Chung, InhoKOR
-52.0
2.5 pts · #30
3Choi, JungwoonKOR
-47.6
3.5 pts · #47

Biggest upsets

R2+247 Elo gap
Choi, Sihwan1516 beat Chung, Junhyeon1763
R4+214 Elo gap
Son, Haseong1426 beat Bae, Jaemin1640
R2+180 Elo gap
Son, Haseong1426 beat Kim, Sunyong1606