Normal kidney function is indicated by blood urea nitrogen test results between 6 and 20 milligrams per deciliter, according to MedlinePlus. Healthy creatinine blood levels are 0.6 to 1.1 milligrams per deciliter for women and 0.7 to 1.3 milligrams per deciliter for men.
The creatinine clearance test compares the amount of creatinine in the urine and blood, MedlinePlus explains. Men with healthy kidneys have scores between 97 and 137 milligrams per minute. Women should have results between 88 and 128 milligrams per minute. The amount of creatinine in the urine is also measured. Normal women's totals run from 11 to 20 milligrams per kilogram of body mass per day. Men's results should be between 14 and 26 milligrams.