A 400-meter track measures 84.39 meters on each straight section and 115.61 meters along each curve, according to the regulations of the International Association of Athletics Federations. Each of the eight lanes on the track is 1.22 meters wide.
The lengths of the straight and curved sections of the track are measured at 30 centimeters from the inside of the track when a curb is present or 20 centimeters from the inside in the absence of a curb. One straight section on a track is extended to accommodate the 100-meter and 110-meter hurdles races. The extended section needs to have at least 3 meters before the starting line and 17 meters after the finish line.
