USCF player statistics

Koster, John

USCF 31930848WashingtonLatest available supplement: Sep 2026
Official US Chess record
Rating format

Regular rating

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550700850Dec 2025: 664 (provisional)Jan 2026: 664 (provisional)Feb 2026: 615 (provisional)Mar 2026: 615 (provisional)Apr 2026: 615 (provisional)May 2026: 615 (provisional)Jun 2026: 615 (provisional)Jul 2026: 787 (provisional)Dec 2025Jul 2026
Published supplement ratings. Lines connect available observations; they do not show individual tournament results.

Published ratings by supplement

All available formats. P indicates a provisional rating.

Monthly USCF ratings for Koster, John
SupplementRegularQuick
Sep 2026——
Aug 2026——
Jul 2026787 P748 P
Jun 2026615 P571 P
May 2026615 P571 P
Apr 2026615 P571 P
Mar 2026615 P571 P
Feb 2026615 P571 P
Jan 2026664 P626 P
Dec 2025664 P626 P

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About these statistics

These pages use the USCF supplements available to Chess67. Ratings can change between monthly publications. Missing months do not mean a player was inactive. For current ratings and tournament history, consult the official US Chess record.

National USCF statisticsWashington USCF statistics