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Thyroid unit converter

Labs in the UK use SI units (pmol/L). US labs use conventional units (ng/dL, pg/mL). If you've seen both and want to compare them - type on either side.

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Thyroid Stimulating Hormone

TSH

Same number in both - these units are equivalent, only the label differs.

Free T4

FT4

pmol/L × 0.0777 = ng/dL

Free T3

FT3

pmol/L × 0.651 = pg/mL

Reverse T3

rT3

Same number in both - these units are equivalent, only the label differs.

Thyroglobulin

Tg

Same number in both - these units are equivalent, only the label differs.

Why aren't antibodies listed here?

Antibody tests TRAb, TPOAb, TgAb are measured differently by each lab and assay - there is no universal conversion factor. Read your result against the reference range printed on your own report.

These tools help you record and make sense of your own information - they don't diagnose, monitor or interpret anything, and they aren't a substitute for medical advice. Where a tool shows a reference range, that is the range from your own lab report, not ours. Everything you enter stays on your device; we never see it. Take what you record to your GP or clinician - only they can tell you what it means for you.