The average bladder capacity of an adult male is 13 to 20 fluid ounces. This is the quantity of liquid voided after severe urgency to urinate, according to Dr. Simon Kimm, Urologist.
Depending on the circumstances, the capacity of the bladder can vary. The capacity can be decreased when ingesting foods or substances that increase the urgency to urinate, causing the bladder to be emptied before reaching normal capacity. The bladder can exceed its normal functional capacity when a person's urgency to urinate is suppressed, such as when the patient is under anesthesia. During surgeries, an average male bladder can become distended and hold up to 33 ounces of liquid.