The urinary bladder is highly distensible and can vary in its capacity. As urine fills the bladder, it can expand to about 5 inches (12 centimeters) long and hold 1 pint (473 milliliters) of urine at moderate capacity. The bladder can expand to twice that capacity if necessary. It usually accumulates 300 to 400 milliliters of urine before emptying, but it can expand to hold 600 to 800 milliliters.