A regulation indoor volleyball court measures 18 meters long and 9 meters wide, split into two equal 9-by-9-meter halves by the net and centerline. Boundary lines — the sidelines running the length of the court and the end lines at each end — are typically 5 centimeters wide and are considered part of the court, so a ball landing on the line is in bounds. Three meters back from the net on each side, the attack line spans the width of the court and marks the boundary between the front zone and back zone, governing where back-row players may legally take off to attack a ball above net height.
A beach volleyball court is smaller, at 16 meters long by 8 meters wide, and has no attack line at all, since with only two players per side, restricting who may attack from where would be impractical — any player may attack from anywhere on a beach court. Surrounding both indoor and beach courts is a free zone of open space, required to be several meters wide at top competition levels, that gives players room to chase down balls that carry them off the court's marked boundaries.
Ceiling height and playing conditions
For indoor competition, regulations also specify a minimum ceiling height above the court — typically at least seven meters at the top international level — so that a served or attacked ball's flight path is never realistically at risk of striking an obstruction overhead.
Line markings players actually watch for
Beyond the basic boundary and attack lines, top-level courts also mark a service zone behind each end line where the server must stand, along with substitution zone markings near the sideline close to the scorer's table that regulate exactly where a substitute must enter and exit the court. These secondary markings rarely draw a casual fan's attention the way the boundary and attack lines do, but they matter enormously to the procedural side of officiating a match correctly.
