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Testosterone Percentile by Age

Enter age and total testosterone, see where that sits against published population data.

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18 to 95
From a morning blood draw
1 nmol/L = 28.84 ng/dL

How This Works

The tool fits a log-normal distribution to the harmonized reference range published by Travison and colleagues in 2017 (264 to 916 ng/dL, the 2.5th to 97.5th percentiles for healthy nonobese men aged 19 to 39). The median shown is derived from those two bounds, not separately reported.

For ages above 40 the whole distribution is lowered by 1 percent per year, the conservative end of what longitudinal studies such as the Baltimore Longitudinal Study of Aging and the Massachusetts Male Aging Study reported. Below 19 the tool uses the 19 to 39 range unchanged.

Two things it does not do. It does not account for body mass index, illness, medication, time of day or assay, all of which move a result. And it does not say whether a number is low for you; that depends on symptoms and repeat testing.

Frequently Asked Questions

Where does the reference range come from?
From Travison and colleagues' 2017 harmonization of four cohort studies in the United States and Europe, which set a 2.5th to 97.5th percentile range of 264 to 916 ng/dL for healthy nonobese men aged 19 to 39. Several large US laboratories adopted that range afterwards.
How is the age adjustment calculated?
The published range covers men aged 19 to 39. For older ages this tool lowers the whole distribution by 1 percent per year from age 40, a conservative figure from longitudinal cohorts that reported declines of roughly 1 to 2 percent a year. It is an approximation; no lab uses this exact adjustment on its report.
Does a low percentile mean I have low testosterone?
No. A diagnosis needs symptoms plus repeated low readings drawn in the morning, often with free testosterone, SHBG, LH and FSH alongside. A single number, including the one you typed here, is context for a conversation with a clinician, not a diagnosis.
Why does my lab's range look different?
Each laboratory sets its own interval for its own assay and reference population. Some print 300 to 1000 ng/dL, some narrower. The number on your report should be read against the range printed next to it.
Is this tool storing my result?
No. The calculation runs in your browser and nothing is sent or saved.

Sources

  1. Travison et al., J Clin Endocrinol Metab 2017;102(4):1161-1173
  2. Harman SM et al. Longitudinal effects of aging on serum total and free testosterone levels in healthy men. J Clin Endocrinol Metab. 2001;86(2):724-731
  3. Feldman HA et al. Age trends in the level of serum testosterone and other hormones in middle-aged men. J Clin Endocrinol Metab. 2002;87(2):589-598
  4. Bhasin S et al. Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018;103(5):1715-1744

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This tool is educational and does not diagnose, treat or recommend any dose. Results depend on the numbers and assumptions you enter. Talk to a licensed clinician about your own results. See the medical disclaimer and terms of use.