Serum Iron — µmol/L to µg/dL

In short To convert serum iron from µmol/L to µg/dL, multiply by 5.5845 — so one µmol/L is 5.5845 µg/dL, and one µg/dL is 0.179067 µmol/L. 60 µg/dL is 10.7 µmol/L; 100 µg/dL is 17.9 µmol/L; 170 µg/dL is 30.4 µmol/L. The factor comes from the molar mass, because iron has an atomic mass of 55.845 g/mol; that is why it differs for every analyte and why a single "lab unit converter" factor does not exist. Note the conventional unit is µg/dL, not mg/dL — there is far less iron in serum than glucose, and using mg/dL by mistake shifts the answer by a factor of a thousand. The same factor applies to total iron-binding capacity, which is reported in the same units and is often on the same line of the report. This converts units. It does not interpret results, does not compare your value against a reference interval, and is not a substitute for the clinician who ordered the test — reference intervals differ between laboratories, methods and populations.