Thyroid Function
Normal range 5-12 µg/dL (64-154 nmol/L SI). Specimen: Serum.
Also known as: T4.
Combined adult band. LabVals does not publish separate men's, women's, or pediatric ranges for Total Thyroxine (Total T4); those can be narrower than the band shown.
| Specimen | Serum |
|---|---|
| Conventional range | 5-12 µg/dL |
| SI range | 64-154 nmol/L |
| Conversion factor | ×12.87 (conventional → SI) |
| Panel | Thyroid Function |
Convert any Total Thyroxine (Total T4) result between units on the unit converter.
The standard teaching reference range for Total Thyroxine (Total T4) is 5-12 µg/dL in conventional units, or 64-154 nmol/L in SI units. This value is measured in serum.
Source: Adult reference values compiled from Pagana & Pagana, Mosby's Diagnostic and Laboratory Test Reference, and Fischbach & Dunning, A Manual of Laboratory and Diagnostic Tests. Reference ranges vary by laboratory, method, age, sex, and population - always use the range printed on the actual result.
Above the range
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Below the range
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