33th iChess Cup
Open SwissStandard
67 players participated in this 6-round tournament, held from 13 Jul 2025 to 20 Jul 2025 in Seoul, South Korea. 3 federations represented. Top 10 Elo average was 1670, and top seed was Jaehyun Sung (🇰🇷 KOR, 1748).
Jaehyun Sung (🇰🇷 KOR, 1748) won with 5.5/6, ahead of Junhyeon Chung (5.5) and Sunwoong Moon (5.0). Sung shared the lead from round 1, winning on tie-break.
The biggest upset came in round 1: Moonso Kim (1446) beat Jinwoo Lee (1698), a +252-point gap.
Location
🇰🇷Seoul, South Korea
Dates
13 Jul 2025 → 20 Jul 2025
Time control
Standard: 60 minutes for game
System
Swiss · 6 rounds
Federations · 3 represented
🇰🇷South Korea×57
🇬🇺Guam×1
🇦🇹Austria×1
Top 3
- 🥇
- 🥈
- 🥉
How it unfolded
Top 6 · 6 roundsTight race until R6; 2 players tied at 5.5/6, decided on Buchholz. Title race narrowed from 3 co-leaders at R4 to 2 at the finish.
Co-leaders
30
14
7
3
2
2
R6 · TIEBREAK CLUSTER
2 players finish on 5.5/6. Sung takes the title on Buchholz Cut1 (22.0).
R6 · HEAD-TO-HEAD · WINNER VS 2ND
Junhyeon Chung drew with Jaehyun Sung (White).
WIN STREAKS · 3 top finishers
Junhyeon Chung 5 wins (R1–R5)Jaehyun Sung 5 wins (R1–R5)Sunwoong Moon 4 wins (R1–R4)
Key matchups · top 4
Head-to-head between the four finishers| Player | 1 | 2 | 3 | 4 |
|---|---|---|---|---|
| 1Junhyeon Chung | * | ½ | — | 1 |
| 2Jaehyun Sung | ½ | * | 1 | — |
| 3Sunwoong Moon | — | 0 | * | — |
| 4Hajoon Kim | 0 | — | — | * |
Grille américaine
| # | Player | Elo | Fed | R1 | R2 | R3 | R4 | R5 | R6 | Pts | Bu C1 | Bu | SB | Perf | Δ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Sung, Jaehyun | 1748 | KOR | +15B | +13N | +5B | +29N | +3B | =2N | 5.5 | 22.0 | 25.0 | 22.25 | 1975 | +23.8 |
| 2 | Chung, Junhyeon | 1631 | KOR | +11B | +20N | +21B | +4N | +8B | =1B | 5.5 | 21.5 | 24.5 | 21.75 | 1982 | +84.8 |
| 3 | Moon, Sunwoong | 1675 | KOR | +34B | +58N | +9B | +7N | −1N | +6B | 5.0 | 20.0 | 21.0 | 15.50 | 1823 | +41.6 |
| 4 | Kim, Hajoon | 1682 | KOR | +28N | +19B | +6N | −2B | +21N | +22B | 5.0 | 18.5 | 21.5 | 16.00 | 1820 | +39.6 |
| 5 | Oh, Jaemin | 1559 | KOR | +33B | +32N | −1N | =19B | +27N | +7B | 4.5 | 18.0 | 20.5 | 13.50 | 1672 | +36.0 |
| 6 | Joo, Eram | 1552 | KOR | +12B | +65N | −4B | +13N | +14B | −3N | 4.0 | 21.0 | 21.0 | 11.00 | 1642 | +20.0 |
| 7 | Chung, Inho | 1494 | KOR | +54B | +10N | +22B | −3B | +9N | −5N | 4.0 | 20.5 | 21.5 | 12.00 | 1671 | +50.0 |
| 8 | Shin, Yisoo | 1620 | KOR | +27N | −46B | +11N | +23B | −2N | +24B | 4.0 | 18.5 | 20.5 | 13.00 | 1566 | -14.0 |
| 9 | Kim, Sunyong | 1554 | KOR | +43N | +30B | −3N | +26B | −7B | +20N | 4.0 | 18.0 | 20.0 | 11.00 | 1525 | -2.8 |
| 10 | You, Eunsung | 1663 | KOR | +57N | −7B | +32N | =14N | +19B | =16B | 4.0 | 16.5 | 17.5 | 10.00 | 1671 | +7.2 |
| 11 | Son, Haseong | 1412 | KOR | −2N | +62B | −8B | +66N | +23N | +21B | 4.0 | 16.5 | 16.5 | 7.00 | 1581 | +35.2 |
| 12 | Choe, Matthew Hajoon | 0 | KOR | −6N | +35B | −13B | +48N | +26N | +25B | 4.0 | 16.0 | 18.0 | 10.50 | 1562 | 0.0 |
| 13 | Ra, Jayden Sanghyuk | 1517 | KOR | +37N | −1B | +12N | −6B | +53N | =14N | 3.5 | 19.5 | 20.5 | 9.25 | 1394 | -16.8 |
| 14 | Pollak, Tony | 1705 | AUT | +50N | =25B | +46N | =10B | −6N | =13B | 3.5 | 16.5 | 18.5 | 9.25 | 1583 | -35.2 |
| 15 | Jeon, Sehyun | 1451 | KOR | −1N | =39B | +37N | −24B | +33N | +35B | 3.5 | 16.0 | 18.0 | 8.50 | 1703 | +24.8 |
| 16 | Lee, Jinwoo | 1698 | KOR | −49B | −33N | +43B | +39N | +28B | =10N | 3.5 | 13.5 | 15.5 | 9.00 | 1513 | -27.6 |
| 17 | Kim, Jio | 1413 | KOR | −29B | −54N | =42B | +40B | +52N | +36N | 3.5 | 11.5 | 12.5 | 7.50 | 1669 | +41.2 |
| 18 | Seo, Yerin | 1543 | KOR | +39B | −53N | +61B | −20N | =32B | +34N | 3.5 | 11.0 | 12.0 | 6.75 | 1448 | -14.8 |
| 19 | Oshiro, Souta | 1516 | KOR | +45B | −4N | +65B | =5N | −10N | =27B | 3.0 | 18.5 | 18.5 | 5.75 | 1382 | -26.4 |
| 20 | Oh, Yechan | 1489 | KOR | +66N | −2B | +41N | +18B | −22N | −9B | 3.0 | 18.0 | 18.0 | 5.50 | 1384 | -19.2 |
| 21 | Kim, Taeu | 1543 | KOR | +60N | +40B | −2N | +53B | −4B | −11N | 3.0 | 17.5 | 18.5 | 4.00 | 772 | -56.0 |
| 22 | Han, Dohoon | 1603 | KOR | +59N | +26B | −7N | F | +20B | −4N | 3.0 | 17.0 | 18.0 | 7.00 | 1526 | -15.6 |
| 23 | Hwang, Noel | 1532 | KOR | −30N | +24B | +59N | −8N | −11B | +40B | 3.0 | 16.0 | 17.0 | 6.00 | 717 | -40.4 |
| 24 | Choi, Sihwan | 0 | KOR | =38B | −23N | +64B | +15N | =25B | −8N | 3.0 | 16.0 | 16.5 | 6.75 | 1458 | 0.0 |
| 25 | Choi, Juneho | 1518 | KOR | +44B | =14N | −38B | +33B | =24N | −12N | 3.0 | 15.5 | 17.5 | 7.75 | 1429 | -9.6 |
| 26 | Shin, Seojun | 1472 | KOR | +55B | −22N | +45B | −9N | −12B | +32N | 3.0 | 15.5 | 16.5 | 5.50 | 1397 | -10.8 |
| 27 | Yim, Jeongbeen | 1408 | KOR | −8B | =64N | +54B | +36N | −5B | =19N | 3.0 | 15.0 | 15.5 | 5.25 | 1455 | +2.4 |
| 28 | Lee, Seoha | 1444 | KOR | −4B | −44N | +56B | +45N | −16N | +41B | 3.0 | 14.5 | 15.5 | 5.00 | 886 | -15.6 |
| 29 | Kim, Junesun | 1637 | GUM | +17N | +51B | +47N | −1B | F | F | 3.0 | 13.0 | 13.0 | 7.50 | 1767 | +26.0 |
| 30 | Jeong, Hyeonwoo | 0 | KOR | +23B | −9N | F | −35B | +42N | +55B | 3.0 | 12.5 | 13.5 | 6.00 | 1448 | 0.0 |
| 31 | Yun, Wooseok | 1605 | KOR | +61B | +49N | +53B | F | F | F | 3.0 | 4.0 | 4.0 | 4.00 | 2245 | +11.6 |
| 32 | Kim, Hyunwoo B | 1438 | KOR | +35N | −5B | −10B | +44N | =18N | −26B | 2.5 | 17.5 | 19.5 | 6.25 | 1420 | -3.6 |
| 33 | Cho, Hayoon | 0 | KOR | −5N | +16B | =36B | −25N | −15B | +53N | 2.5 | 17.0 | 18.0 | 5.75 | 1392 | 0.0 |
| 34 | Han, Wontae | 1439 | KOR | −3N | =37B | =39N | +41B | =35N | −18B | 2.5 | 15.5 | 17.5 | 5.50 | 1350 | -11.6 |
| 35 | Lee, Chanjoo | 1643 | KOR | −32B | −12N | +60B | +30N | =34B | −15N | 2.5 | 15.5 | 16.5 | 5.25 | 1164 | -73.6 |
| 36 | An, Seunggi | 1518 | KOR | −40N | +43B | =33N | −27B | +55N | −17B | 2.5 | 13.0 | 14.0 | 4.25 | 626 | -48.8 |
| 37 | Lim, Seonghyeon | 0 | KOR | −13B | =34N | −15B | =42N | +65B | =?N | 2.5 | 11.5 | 11.5 | 2.25 | 1271 | 0.0 |
| 38 | Bae, Jaemin | 1548 | KOR | =24N | +41B | +25N | F | F | F | 2.5 | 8.0 | 8.0 | 6.50 | 2322 | +19.2 |
| 39 | Hwang, Jiu | 0 | KOR | −18N | =15N | =34B | −16B | −41N | +66B | 2.0 | 15.0 | 15.0 | 3.00 | 1337 | 0.0 |
| 40 | Lee, Seungjun | 0 | KOR | +36B | −21N | −?B | −17N | +43B | −23N | 2.0 | 14.0 | 14.0 | 4.50 | 1255 | 0.0 |
| 41 | Park, Sejin A | 0 | KOR | +?B | −38N | −20B | −34N | +39B | −28N | 2.0 | 13.0 | 13.0 | 2.00 | 1238 | 0.0 |
| 42 | FIDE 13234994 | 0 | — | −46N | −59B | =17N | =37B | −30B | +63N | 2.0 | 12.0 | 13.0 | 4.00 | 1246 | 0.0 |
| 43 | Cho, Jungbin | 0 | KOR | −9B | −36N | −16N | +?B | −40N | +?B | 2.0 | 12.0 | 12.0 | 0.00 | 780 | 0.0 |
| 44 | Lim, Chanhee | 0 | KOR | −25N | +28B | −51N | −32B | −?N | +?B | 2.0 | 10.5 | 10.5 | 3.00 | 1253 | 0.0 |
| 45 | Moon, Changjun | 0 | KOR | −19N | +57B | −26N | −28B | −?N | +65B | 2.0 | 10.0 | 10.0 | 1.00 | 1274 | 0.0 |
| 46 | Maeng, Chihyun | 1483 | KOR | +42B | +8N | −14B | F | F | F | 2.0 | 9.5 | 9.5 | 6.00 | 1663 | +20.4 |
| 47 | Jeong, Yoojin | 1519 | KOR | +56B | +48N | −29B | F | F | F | 2.0 | 9.0 | 9.0 | 3.00 | 842 | -13.2 |
| 48 | Yun, Yejoon | 0 | KOR | F | −47B | −50N | −12B | +57N | +?B | 2.0 | 9.0 | 9.0 | 1.00 | 1346 | 0.0 |
| 49 | Kim, Moonso | 1446 | KOR | +16N | −31B | +55N | F | F | F | 2.0 | 7.5 | 7.5 | 4.50 | 1652 | +20.8 |
| 50 | Jin, Soohyeon | 1447 | KOR | −14B | +56N | +48B | F | F | F | 2.0 | 6.5 | 6.5 | 3.00 | 904 | -7.2 |
| 51 | Choi, Jungwoon | 1493 | KOR | +64B | −29N | +44B | F | F | F | 2.0 | 5.5 | 5.5 | 2.50 | 842 | -18.8 |
| 52 | Park, Sihun | 1483 | KOR | F | F | F | +60N | −17B | +56N | 2.0 | 5.5 | 5.5 | 2.00 | 610 | -24.4 |
| 53 | Shin, Yijoon | 0 | KOR | F | +18B | −31N | −21N | −13B | −33B | 1.0 | 15.5 | 15.5 | 3.50 | 1360 | 0.0 |
| 54 | FIDE 13231049 | 0 | — | −7N | +17B | −27N | F | F | F | 1.0 | 10.5 | 10.5 | 3.50 | 1321 | 0.0 |
| 55 | Suh, Hannah | 0 | KOR | −26N | F | −49B | +65N | −36B | −30N | 1.0 | 10.5 | 10.5 | 0.00 | 671 | 0.0 |
| 56 | Kim, Howon | 0 | KOR | −47N | −50B | −28N | +57B | −?N | −52B | 1.0 | 10.0 | 10.0 | 1.00 | 1229 | 0.0 |
| 57 | Jang, Seyong | 1439 | KOR | −10B | −45N | −62B | −56N | −48B | +67B | 1.0 | 10.0 | 10.0 | 0.00 | 853 | -9.6 |
| 58 | Lee, Donghwa | 1496 | KOR | +62N | −3B | F | F | F | F | 1.0 | 9.0 | 9.0 | 1.00 | 872 | -12.8 |
| 59 | An, Teaha | 0 | KOR | −22B | +42N | −23B | F | F | F | 1.0 | 8.0 | 8.0 | 2.00 | 760 | 0.0 |
| 60 | FIDE 13234978 | 0 | — | −21B | −?N | −35N | −52B | −?B | +?N | 1.0 | 7.5 | 7.5 | 0.00 | 747 | 0.0 |
| 61 | Kim, Yeonseo | 1402 | KOR | −31N | +66B | −18N | F | F | F | 1.0 | 6.5 | 6.5 | 0.00 | 772 | 0.0 |
| 62 | FIDE 13223488 | 0 | — | −58B | −11N | +57N | F | F | F | 1.0 | 6.0 | 6.0 | 1.00 | 1342 | 0.0 |
| 63 | FIDE 13234943 | 0 | — | F | F | F | −?B | +?N | −42B | 1.0 | 2.0 | 2.0 | 0.00 | 655 | 0.0 |
| 64 | Park, Seojin A | 0 | KOR | −51N | =27B | −24N | F | F | F | 0.5 | 8.0 | 8.0 | 1.50 | 1337 | 0.0 |
| 65 | FIDE 13234986 | 0 | — | F | −6B | −19N | −55B | −37N | −45N | 0.0 | 12.5 | 12.5 | 0.00 | 731 | 0.0 |
| 66 | FIDE 13235001 | 0 | — | −20B | −61N | F | −11B | −?N | −39N | 0.0 | 10.0 | 10.0 | 0.00 | 645 | 0.0 |
| 67 | FIDE 13230999 | 0 | — | F | F | F | −?B | −?B | −57N | 0.0 | 1.0 | 1.0 | 0.00 | 651 | 0.0 |
Key insights
Biggest movers and upsets — the story behind the numbers.
Top rating gainers
- 1Chung, JunhyeonKOR+84.85.5 pts · #1
- 2Chung, InhoKOR+50.04.0 pts · #8
- 3Moon, SunwoongKOR+41.65.0 pts · #3
Top rating losers
- 1Lee, ChanjooKOR-73.62.5 pts · #48
- 2Kim, TaeuKOR-56.03.0 pts · #66
- 3An, SeunggiKOR-48.82.5 pts · #63
Biggest upsets
- R1+252 Elo gap
- R1+205 Elo gap
- R6+192 Elo gap