Normal testosterone levels for adult men fall between 264 and 916 ng/dL, based on the harmonized reference range established by the Endocrine Society for healthy, non-obese men aged 19 to 39. For adult women, the normal range is much lower: 8 to 60 ng/dL. These numbers can vary depending on the lab, your age, your weight, and even the time of day your blood is drawn.
Normal Ranges for Men
The most widely cited reference range for men comes from the Endocrine Society’s 2018 clinical practice guideline, which used standardized lab methods to measure testosterone in healthy young men. Using the broadest cutoffs (2.5th to 97.5th percentile), the range is 264 to 916 ng/dL. A slightly narrower range, 303 to 852 ng/dL, captures the 5th to 95th percentile. Cleveland Clinic lists 193 to 824 ng/dL for men aged 18 to 99.
The differences between these numbers reflect different lab methods and population samples. Your own lab report will print a reference range specific to the assay it uses, and that’s the range your doctor will compare your result against. A reading of 280 ng/dL might be flagged as low by one lab and normal by another, which is why context matters more than any single cutoff.
The Endocrine Society considers 264 ng/dL the lower limit of normal for young men. Below that threshold, combined with symptoms like fatigue, low sex drive, or loss of muscle mass, a diagnosis of low testosterone (hypogonadism) may be considered. A number alone doesn’t confirm a problem. Diagnosis requires low levels on at least two separate morning blood draws plus symptoms that affect quality of life.
Normal Ranges for Women
Women produce testosterone too, just in smaller amounts. The normal range for adult women 19 and older is 8 to 60 ng/dL. Testosterone in women supports bone density, muscle maintenance, and sex drive. Levels that are too high can signal conditions like polycystic ovary syndrome (PCOS), while levels that are too low sometimes contribute to low energy and reduced libido, particularly after menopause.
Free vs. Total Testosterone
Most testosterone in your blood is bound to proteins, primarily one called sex hormone-binding globulin (SHBG). Only a small fraction circulates “free,” meaning it’s available for your body to use. A standard blood test measures total testosterone, which includes both bound and free. Free testosterone has its own reference range: roughly 50 to 200 pg/mL for men, measured in picograms rather than nanograms because the amount is so small.
Free testosterone matters because two people can have the same total number but very different amounts of usable hormone. If your SHBG is unusually high (which can happen with aging, liver conditions, or certain medications), your total testosterone might look fine while your free testosterone is actually low. That’s why doctors sometimes order a free testosterone test or calculate it from your total and SHBG levels when symptoms don’t match the initial result.
How Testosterone Changes With Age
Testosterone peaks in late adolescence and early adulthood, then gradually declines. During puberty, levels rise dramatically through each stage of development. Boys in the earliest stage of puberty have just 2 to 23 ng/dL. By mid-puberty, levels can reach 280 ng/dL. By the final stage, the range (265 to 800 ng/dL) closely mirrors adult values.
After about age 30, total testosterone drops roughly 1% to 2% per year for most men. This decline is slow enough that many men stay well within the normal range into their 60s and 70s, while others dip below 264 ng/dL and start noticing symptoms. A low reading in a 65-year-old doesn’t automatically mean something is wrong; it may simply reflect normal aging. What matters is whether the level is low enough to cause problems you can feel.
Why Your Result Might Be Lower Than Expected
Body weight is one of the biggest modifiers. Testosterone levels in men with obesity are often reduced in proportion to the degree of excess weight. This happens primarily because excess body fat lowers SHBG, the carrier protein that transports testosterone through the blood. When SHBG drops, measured total testosterone drops with it, even though the body’s actual hormonal signaling may be functioning normally. Researchers describe this as “pseudo-hypogonadism of obesity” because the brain’s hormonal feedback loops (reflected by normal LH and FSH levels) confirm the body isn’t truly deficient.
This distinction has practical consequences. For men whose low readings are driven by weight rather than a true hormonal disorder, the most effective treatment is weight loss, not testosterone therapy. Clinically significant weight loss through diet, lifestyle changes, medication, or surgery can produce substantial increases in measured testosterone. Testosterone treatment in this group carries risks without clear benefit.
Other factors that can temporarily lower your result include poor sleep, high stress, heavy alcohol use, and certain medications like opioids or corticosteroids. Acute illness can also suppress levels for weeks.
When and How Testing Works
Testosterone follows a daily rhythm. Levels peak between 7 and 10 AM and hit their lowest point around 7 PM. Because of this swing, guidelines recommend a fasting blood draw between 8 and 10 AM for the most accurate result. A test done in the afternoon could read meaningfully lower than a morning draw in the same person, potentially leading to a misleading result.
If your first test comes back low, expect your doctor to repeat it on a different day before drawing any conclusions. A single low reading can result from a bad night’s sleep, recent illness, or normal day-to-day variation. Two consistently low morning values, paired with symptoms, form the basis for a diagnosis.
Labs may report your result in either ng/dL or nmol/L. To convert, multiply ng/dL by 0.0347 to get nmol/L. So 264 ng/dL equals about 9.2 nmol/L, and 916 ng/dL equals about 31.8 nmol/L. If your lab report uses nmol/L, those are the boundaries to keep in mind.