ng/dL vs nmol/L

If you’ve watched YouTube videos, listened to podcasts, or read international articles about testosterone, you’ve probably noticed that most of them use US-based measurement units. In Australia, however, testosterone results are reported differently — which can make comparisons confusing.

In the United States, laboratories usually express total testosterone in nanograms per decilitre (ng/dL) and free testosterone in picograms per millilitre (pg/mL).
In Australia and most of Europe, testosterone levels are reported in nanomoles per litre (nmol/L) for total testosterone and picomoles per litre (pmol/L) for free testosterone.

Because of these differences, understanding how to convert between units can help you interpret or compare test results correctly.

Conversion Formulas

• Total Testosterone:
  To convert from ng/dL to nmol/L, divide by 28.85.
  Example: 900 ng/dL ÷ 28.85 = ~31.2 nmol/L

• Free Testosterone:
  To convert from pg/mL to pmol/L, divide by 0.2885.
  Example: 20 pg/mL ÷ 0.2885 = ~69 pmol/L

For quick mental estimates, dividing by 30 for total testosterone provides an easy and reasonably accurate approximation.

Why This Matters

Understanding these conversions can make it easier to follow discussions in international videos or research papers about testosterone. However, keep in mind that reference ranges vary by lab, and “normal” levels depend on age, assay methods, and clinical context.

Always discuss your individual results with a qualified doctor, as interpretation requires professional evaluation of symptoms, history, and laboratory data.

This article is for educational purposes only and does not replace professional medical advice or diagnosis. Always consult an AHPRA-registered healthcare provider for guidance specific to your health and blood test results.