The size of the kidney depends on body size. A normal adult male kidney will be at least 11 centimeters long. A normal adult female kidney will be at least 10 centimeters long. The right kidney is often just slightly longer than the left kidney.
The size of kidney stones
determine the time needed for their removal from the kidneys. Smaller the size of a stone, the faster it can pass through the urinary tract. For example, a 2 mm stones may pass through the kidneys in about 12 days but stones of size 4 mm can take about 30 days to pass out.