The average range of the Blood Urea Nitrogen Test is 7-17 mg/dL.

However, the normal ranges differ from lab to lab. Based on those, the high range or low range is calculated. Urea levels also increase with age, so infants have a lower range.

The normal values and reference ranges of the test may vary from lab to lab. Please refer to the ranges mentioned in the report and consult a doctor to understand the interpretation of lab reports.