Free T3 Test
The active, unbound form of T3 — the most metabolically active thyroid hormone.
What is Free T3?
The active, unbound form of T3 — the most metabolically active thyroid hormone.
Free T3 Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+ | 2.00 – 4.40 pg/mL |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
Sources
Related Thyroid biomarkers
Markers commonly tested alongside Free T3.
Frequently asked
No. TestWell's licensed physician network reviews and approves your order — usually within minutes. You can place an order online without an in-person visit or a referral from your own doctor.
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