Question: is 5 mm a big kidney stone?
Answer: The smaller the kidney stone, the more likely it will pass on its own. If it is smaller than 5 mm (1/5 inch), there is a 90% chance it will pass without further intervention. If the stone is between 5 mm and 10 mm, the odds are 50%. If a stone is too large to pass on its own, several treatment options are available.