yeah, roughly speaking...
small bales are rectangular, approx 40 x 45 x 100cm and weigh 25-30kg.
round bales are approx 1.5 wide and 1.2-1.8m in diameter, weighing in at 400-600kg
large bales are rectangular, approx 90cm x 1m x 2.4m and weigh 500-700kg.
weight will depend on how dry the material is and the density the baler was set at - and many modern rotobalers (rounds) or large square balers are adjustable as to physical size of bale.