In official international competitions, including the Olympics, the ball used for table tennis matches must have a 40mm diameter, weigh 2.7 g, and be either orange or white in color. The brand of the ball must be a brand approved by the International Table Tennis Federation (ITTF). The Olympic Committee wants to stay in line with the ITTF, so that an international standard is maintained as far as which balls are used for tournaments.
In approving a candidate ball for international competition, there are four main categories in which balls are tested. These include qualitative criteria and appearance, quantitative criteria, marking, and administrative items. Qualitative criteria includes the ball's appearance, seam, stamp, and packaging. The quantitative criteria includes numerical specifications for the ball, like weight and size. The marking describes the qualities like the brand and date code. Finally, the balls must be approved with specific ITTF specification codes and marks.
Both men and women use the same ball for table tennis in the Olympics. All regulations for the ball are those followed by the ITTF, and there are no differences between men's and women's equipment for competition.