The range is 4.5 to 8, but urine is commonly acidic (ie 5.5-6.5) due to metabolic activity. Acidic urine (low pH) may be caused by diet (eg, acidic fruits such as cranberries) and uric acid calculi. Urine pH generally reflects the blood pH but in renal tubular acidosis (RTA) this is not the case. https://www.google.co.uk/?gws_rd=ssl#q=urine+ph