Hormone unit converter
US labs report hormones in mass units (ng/dL, pg/mL); most of the world uses SI molar units (nmol/L, pmol/L) — and the same blood level reads as a completely different number. Pick a hormone and type in either box to convert instantly, with the exact lab factor shown every time.
1 ng/dL = 0.035 nmol/L · 1 nmol/L = 28.84 ng/dL
Adult male total T harmonizes to roughly 264–916 ng/dL (≈ 9.2–31.8 nmol/L) in healthy young men.
Why the units matter
A testosterone of 500 ng/dL and 17.3 nmol/L are the same result — one in US conventional units, one in SI. If you compare a US lab value against an international reference range, a research paper, or a clinic abroad without converting, the numbers won’t line up and a normal level can look alarmingly high or low. The conversion is just the hormone’s molecular weight: testosterone ng/dL × 0.03467 = nmol/L; estradiol pg/mL × 3.671 = pmol/L. For what the numbers actually mean, see testosterone levels by age, and to estimate the active fraction from a total reading use the free testosterone calculator.
Common questions
- How do you convert testosterone from ng/dL to nmol/L?
- Multiply ng/dL by 0.03467 to get nmol/L (and divide by 0.03467 — i.e. multiply by 28.84 — to go the other way). So 500 ng/dL ≈ 17.3 nmol/L, and 20 nmol/L ≈ 577 ng/dL. The factor comes from testosterone's molecular weight (288.4 g/mol). This tool does it both ways for you.
- How do you convert estradiol from pg/mL to pmol/L?
- Multiply pg/mL by 3.671 to get pmol/L (divide by 3.671 to reverse). So 30 pg/mL ≈ 110 pmol/L. US labs usually report estradiol in pg/mL while most of the world uses pmol/L.
- Why do US and international lab results use different units?
- US labs report hormones in 'conventional' mass units (ng/dL, pg/mL, µg/dL), while most other countries use SI molar units (nmol/L, pmol/L). The numbers look completely different for the same blood level — which is why comparing a US result to an international reference range, or to a study, requires converting first.
- Does SHBG need converting?
- No — SHBG (sex-hormone-binding globulin) is reported in nmol/L essentially everywhere, so there's no conventional-vs-SI conversion. It's included here for convenience alongside the other hormones, and it's a key input to the free testosterone calculation.
- Are the reference ranges here diagnostic?
- No. The typical adult ranges shown are for orientation only — actual reference ranges are assay- and lab-specific, vary by age and sex, and a single value is never a diagnosis. Always compare against your own lab's range and discuss results with a clinician.