Thyroxine— Normal Range & What Your Result Means

Thyroid hormone

Normal Thyroxine range (T4, μg/dL)

  • Adults4.5–11.2 μg/dL

Ranges are typical adult values and vary between labs. Use the range on your own report.

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What is Thyroxine (T4)?

Thyroxine is measured as part of a thyroid panel. Your T4 is normal.

What does a high Thyroxine mean?

Elevated T4 with low TSH suggests hyperthyroidism.

What does a low Thyroxine mean?

Low T4, especially with high TSH, confirms hypothyroidism. Your thyroid isn't producing enough hormone.

Understand your whole report, not just one number

A single value rarely tells the full story — Thyroxine is best read alongside the rest of your panel. Paste your values or upload your report and get a plain-English explanation of every marker, with the important results flagged.

Thyroxine: frequently asked questions

What is a normal Thyroxine level?

A normal Thyroxine (T4) level is 4.5–11.2 μg/dL for adults. Reference ranges vary slightly between laboratories, so always compare against the range printed on your own report.

What does a high Thyroxine mean?

Elevated T4 with low TSH suggests hyperthyroidism.

What does a low Thyroxine mean?

Low T4, especially with high TSH, confirms hypothyroidism. Your thyroid isn't producing enough hormone.

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