Wins
170
Indexed tournament wins
Player record
Koh, Chason
Losses
210
Indexed tournament losses
Matches
380
Decisive results
Win rate
44.7%
Across indexed matches
Peak rating
1,859
Highest rating in the available history.
Biggest upset
Chui, Lim Ming
2002 Meiklejohn Nat Sr TTT · Jun 9, 2002 · +362 rating
Open →Biggest loss
Tentor, John
2004 USA Nationals Championship · Dec 18, 2004 · -578 rating
Open →Most frequent opponent
Koshimoto, Hiroshi
8 matches
Open →Rating trajectory
Published rating movement across recorded events.
Tournament history
53 tournament appearances · synced Aug 9, 2026, 2:20 AM
| Date | Tournament | Rating in | Rating after | Points changed | Record |
|---|---|---|---|---|---|
| Mar 25, 2001 | 2001 Arizona OpenTournament · View matches | 1,667 | 1,790 | +123 | 11W / 5L |
| Feb 25, 2001 | Golden Western Open - CATournament · View matches | 1,727 | 1,667 | -60+1 / -61 | 2W / 4L |
| Dec 2, 2000 | Valley of the Sun OpenTournament · View matches | 1,703 | 1,727 | +24+57 / -33 | 6W / 7L |
| Oct 6, 2000 | Western Open on the No American TourTournament · View matches | 1,685 | 1,703 | +18+21 / -3 | 2W / 6L |
| Sep 17, 2000 | Lake Havasu OpenTournament · View matches | 1,651 | 1,685 | +34 | 9W / 6L |
| Sep 10, 2000 | Pacific Coast OpenTournament · View matches | 1,750 | 1,651 | -99+0 / -99 | 1W / 7L |
| Jun 25, 2000 | California State OpenTournament · View matches | 1,754 | 1,750 | -4+0 / -4 | 2W / 3L |
| Jun 11, 2000 | High Desert InvitationalTournament · View matches | 1,742 | 1,754 | +12+15 / -3 | 2W / 2L |
| Jun 4, 2000 | Meiklejohn National Senior TTTTournament · View matches | 1,740 | 1,742 | +2+9 / -7 | 5W / 5L |
| May 7, 2000 | San Diego Spring OpenTournament · View matches | 1,698 | 1,740 | +42 | 6W / 7L |
| Feb 27, 2000 | Arizona OpenTournament · View matches · USATT readjusted 1,619 → 1,675 | 1,619 | 1,698 | +23+42 / -19 | 6W / 2L |
| Feb 6, 2000 | Golden Western States OpenTournament · View matches | 1,660 | 1,619 | -41+0 / -41 | 2W / 2L |
| Dec 19, 1999 | US NationalsTournament · View matches | 1,660 | 1,660 | 0+53 / -53 | 6W / 5L |
| Dec 11, 1999 | 1999 4th Annual US Nationals WTournament · View matches | 1,662 | 1,660 | -2+3 / -5 | 1W / 5L |
| Nov 7, 1999 | High Desert OpenTournament · View matches | 1,636 | 1,662 | +26 | 3W / 2L |
| Sep 12, 1999 | Pacific Coast OpenTournament · View matches | 1,645 | 1,636 | -9+2 / -11 | 3W / 2L |
| Jun 27, 1999 | California State OpenTournament · View matches | 1,642 | 1,645 | +3+17 / -14 | 2W / 3L |
| Jun 13, 1999 | Meiklejohn National Seniors TTTournament · View matches | 1,678 | 1,642 | -36 | 1W / 4L |
| May 1, 1999 | Sun City Open Senior TTTTournament · View matches | 1,667 | 1,678 | +11+18 / -7 | 4W / 2L |
| Apr 25, 1999 | Thousand Oaks ClassicTournament · View matches | 1,638 | 1,667 | +29+30 / -1 | 1W / 4L |