Back to Ratings.

NASPA Rating Calculator

Enter all required information as indicated, then click on the Calculate button to see a player’s new rating after a tournament. If a player has not played fifty games in his or her career, their rating will change by a greater amount; this is taken into account if you specify the player by name and not by rating.

Players may earn feedback bonus points for playing opponents who earned acceleration bonus points: this tool does not perform this calculation.

You may also want to use the tsh tournament management program, which includes the code libraries used to compute official ratings.

Comments or questions concerning this tool should be sent to John Chew. A basic introduction to the rating system is also available on this web site.

Result will appear here.


Enter the player’s name or rating.


Enter the number of wins, counting ties as 0.5 each.

Tournament Type

Ratings changes at Local Club Tournaments (LCTs) are one third of the changes at Open Rated Tournaments (ORTs).


Enter opponent names or ratings. Names must be entered on their own line and exactly as shown in the ratings list (last name first); multiple ratings may be entered on a line. If the player played someone more than once, enter their name or rating once for each time they played them.