What is the bilirubin level?

Bilirubin levels are an important reference for assessing liver and biliary tract function. The normal range for total bilirubin is 1.71–17.1 μmol/L; for direct (conjugated) bilirubin, it is 0–6.8 μmol/L; and for indirect (unconjugated) bilirubin, it is 1.7–13.7 μmol/L. Indirect bilirubin primarily reflects the liver’s capacity for bilirubin conjugation; elevated levels may indicate jaundice or impaired liver function. Direct bilirubin mainly reflects the biliary excretion function; its elevation may suggest biliary obstruction. As the sum of direct and indirect bilirubin, total bilirubin is a key indicator for evaluating the severity of jaundice and for assessing hepatic and biliary function. If abnormal bilirubin results are detected, there is no need for excessive concern; however, prompt medical consultation is recommended to complete relevant diagnostic tests, establish a definitive diagnosis, and initiate timely and appropriate treatment—thereby preventing disease progression or delay in management.