Testosterone Levels by Age

What's Normal — And What's Not

Testosterone levels aren't static. They peak in your late teens to early 20s, plateau through your 30s, and then tend to decline gradually. In the Massachusetts Male Aging Study, total testosterone in men aged 40–70 fell by about 1.6% per year within the same individuals over 7–10 years of follow-up (Feldman et al., 2002). Population snapshots show a smaller drop between age groups, as the tables below show.

Not sure which markers you need? See our guide to the at-home male hormone test and which markers actually matter.

Testosterone Levels by Age: Published Percentiles (ng/dL)

The tables below reproduce total testosterone percentiles exactly as published in peer-reviewed studies whose measurements were standardized to the CDC reference method. All values are total testosterone in ng/dL (1 ng/dL = 0.0347 nmol/L). Nothing here comes from Heyday patients; each number links to its source.

Nonobese men, by age (Travison et al., 2017)

Source: Travison et al., J Clin Endocrinol Metab 2017, Table 4. Model-based estimates (constrained quantile regression) from four community cohorts — the Framingham Heart Study, Osteoporotic Fractures in Men Study and Male Sibling Study of Osteoporosis (US) and the European Male Aging Study — after each cohort's assay was cross-calibrated to the CDC reference method.

All men, by age (Travison et al., 2017)

Source: Travison et al., J Clin Endocrinol Metab 2017, Table 4. Same cohorts and method as above, including men with obesity.

US men aged 20–44 (NHANES 2011–2016)

Source: Zhu et al., J Urol 2022, analysis of nationally representative NHANES 2011–2016 data. Excluded men on hormonal medications, with a history of testicular cancer or orchiectomy, and with afternoon or evening blood draws. The authors used the American Urological Association's "middle tertile" definition of a normal level.

For the US adult male population as a whole, with no health exclusions, CDC scientists reported a 10th–90th percentile range of 150–698 ng/dL in men aged 20 and older from NHANES 2011–2012 (Vesper et al., Clin Chem 2015). That sample was not restricted by health status, and the authors note it likely included men using testosterone therapy.

How to read these numbers: they describe populations, not individuals. Your lab's reference range depends on its assay, and a single result does not diagnose anything on its own. Morning timing, repeat testing and symptoms all matter, and only a licensed clinician can interpret a result.

The American Urological Association guideline uses total testosterone below 300 ng/dL as a reasonable cut-off in support of a low testosterone diagnosis, alongside symptoms. But "normal range" is broad — a 40-year-old at 310 ng/dL is technically in range but may feel terrible, while another at 500 ng/dL feels great. Context matters as much as the number.

Total vs. Free Testosterone

Total testosterone measures all testosterone in your blood — both bound (to SHBG and albumin) and unbound. Free testosterone measures only the unbound fraction, which is the portion actually available for your body to use. You can have a normal total T but low free T if your SHBG is elevated, which is common in aging men. This is why a comprehensive panel testing both values is essential for accurate diagnosis.

Why "Normal Range" Can Be Misleading

Reference ranges on lab reports reflect a statistical distribution, not an ideal. The widely cited 264–916 ng/dL range, for example, is the 2.5th to 97.5th percentile of healthy nonobese men aged 19–39 (Travison et al., 2017), while other labs base their ranges on different assays and populations. Being at the 5th percentile is technically "normal" but tells you nothing about whether YOUR level is optimal for YOUR body and symptoms. A good provider treats the patient, not just the lab number.

When to Get Tested

Any man over 30 experiencing fatigue, low libido, mood changes, weight gain, or cognitive decline should get a comprehensive hormone panel. Testing should be done in the morning (before 10am) when levels peak, and ideally confirmed with a second draw if the first result is low.

Sources

1. Travison TG, Vesper HW, Orwoll E, et al. Harmonized Reference Ranges for Circulating Testosterone Levels in Men of Four Cohort Studies in the United States and Europe. J Clin Endocrinol Metab. 2017;102(4):1161–1173. doi:10.1210/jc.2016-2935. Full text (PMC5460736)
2. Zhu A, Andino J, Daignault-Newton S, et al. What Is a Normal Testosterone Level for Young Men? Rethinking the 300 ng/dL Cutoff for Testosterone Deficiency in Men 20–44 Years Old. J Urol. 2022;208(6):1295–1302. doi:10.1097/JU.0000000000002928. PubMed 36282060
3. Vesper HW, Wang Y, Vidal M, Botelho JC, Caudill SP. Serum Total Testosterone Concentrations in the US Household Population from the NHANES 2011–2012 Study Population. Clin Chem. 2015;61(12):1495–1504. doi:10.1373/clinchem.2015.245969. PubMed 26510959
4. Feldman HA, Longcope C, Derby CA, et al. Age Trends in the Level of Serum Testosterone and Other Hormones in Middle-Aged Men: Longitudinal Results from the Massachusetts Male Aging Study. J Clin Endocrinol Metab. 2002;87(2):589–598. doi:10.1210/jcem.87.2.8201. PubMed 11836290
5. American Urological Association. Evaluation and Management of Testosterone Deficiency (AUA Guideline). auanet.org

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