Some claim Erathostenes used the Egyptian stade of 157.5 meters , which would imply a circumference of 39,690 km , an error of 1.6 % , but the 185 meter Attic stade is the most commonly accepted value for the length of the stade used by Eratosthenes in his measurements of the Earth , which imply a circumference of 46,620 km , an error of 16.3 % .
The common Attic stadium was about 185 m , which would imply a circumference of 46,620 km , which is 16.3 % too large .