A free or total triiodothyronine (free T3 or total T3) test is used to assess thyroid function.
It is ordered primarily to help diagnose hyperthyroidism and may be ordered to help monitor treatment of a person with a known thyroid disorder. T3 and T4 (thyroxine) are hormones produced by the thyroid gland.
Normal range of T3 Test is 75 -200 ng/dL.