The following rules are from USA Table Tennis, the governing body of Table Tennis in the United States:
Scoring and Games
– Games are played to 11 points
– Players serve two serves each, alternating. A player does not have to win specifically off their own serve in order to win a point
– If a game ties at 10-10, a player must win by 2 points. In this situation, players serve one serve each, alternating
– In competition, games are played best of 5 (first to win 3 games) or best of 7 (first to win 4 games). Social games can also be played best of 3 (first to win 2 games)
Legal Serving
– You must throw the ball up straight, from a flat palm, at least 6 inches (16cm)
– Your toss and service contact must be behind the table surface (not over)
– You cannot hide the ball from the ball toss to contact, with any part of your body
– If the ball hits the net during service, it is a let, the point is replayed. There is no limit or point deductions for let serves.
Equipment Basics
– A table tennis racket must be one side black, one side (recently approved) any approved color
– The official approved ball is the 40mm+ plastic ball
– The dimensions of an approved table tennis table are: 9ft long, 5ft wide, 2.5ft high
– The approved height of a table tennis net is: 6 inches