A measuring device includes a measuring mechanism, a counting mechanism, a variable transmission gear assembly disposed between the measuring mechanism and the counting mechanism, and an adjustment member that engages at the gear assembly for changing the transmission ratio. The gear assembly includes a first shaft and a second shaft which are arranged parallel to one another. First and second out-of-round toothed spur gears are seated on the first shaft. An overrunning clutch is disposed between each one of the first and second spur gears and the first shaft, both overrunning clutches acting in the same direction of rotation. Third and fourth out-of-round spur gears are seated on the second shaft and mesh with the respective first and second spur gears. The third spur gear is rigidly fastened on the second shaft. The fourth spur gear is rotatably mounted on the second shaft. A device for turning the fourth spur gear about a limited adjustment angle relative to the second shaft changes the transmission ratio is actuated by the adjustment member.