What makes a serve legal?

Under Law 2.6 of the Laws of Table Tennis (ITTF Statutes 2026):

1. Start with the ball resting freely on the open palm of your stationary free hand.
2. Project it near vertically upwards, without spin, so it rises at least 16 cm after leaving your palm, and falls without touching anything before you hit it.
3. Hit it as it falls, so it touches your court first and then goes directly to the receiver's court (in doubles, right half-court to right half-court).
4. From the start of the serve until you hit it, the ball must be above the level of the playing surface and behind your end line (which counts as extending indefinitely sideways).
5. The ball must not be hidden from the receiver by you, your doubles partner or anything you wear or carry.
6. As soon as the ball is projected, move your free arm and hand out of the space between the ball and the net.

It's your responsibility to serve so the umpire or assistant umpire can see the serve is legal, and either can call it incorrect. If an official isn't sure, they may, on the first occasion in a match, stop play and warn you; after that, any serve by you or your doubles partner that isn't clearly legal is a fault.

The umpire may relax these requirements where a physical disability prevents a player from complying.