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TSH Unit Converter
Thyroid-Stimulating Hormone (TSH), also known as thyrotropin, is produced by the pituitary gland to regulate the thyroid’s production of hormones T3 and T4. It is the first-line screening test for thyroid dysfunction.
TSH reporting units are highly standardized compared to other hormones. The international unit (mIU/L) is numerically identical to the mass/volume unit (μIU/mL) often used in some regions. This converter confirms that equivalence.
International Units
StandardMilli-International Units per Liter (SI Standard).
Other Units
Micro-International Units per Milliliter.
Clinical Context
Reference Ranges (Adults): Typically 0.4 – 4.0 mIU/L.
Note: Ranges vary by trimester during pregnancy and by age.
Interpretation:
• High TSH: Usually indicates Primary Hypothyroidism (thyroid underactive).
• Low TSH: Usually indicates Primary Hyperthyroidism (thyroid overactive) or pituitary failure (Secondary Hypothyroidism).
Conversion Logic:
1 mIU/L = 1 μIU/mL.
The conversion factor is 1.0.
Clinical References
How to Use This Converter
Follow these steps to normalize TSH values.
Enter Values
Input your laboratory result into the corresponding unit field (e.g., mIU/L).
Automatic Conversion
The calculator instantly updates the other field. For TSH, the numeric value remains the same.
Reset
Use the Clear button to reset all fields.
Frequently Asked Questions
Yes. 1 milli-international unit per liter is numerically identical to 1 micro-international unit per milliliter.
A high TSH usually means your thyroid gland is not producing enough hormone (hypothyroidism), so the pituitary is working harder to stimulate it.
