Is my Testosterone (Total) normal?
Free blood test checker · Standard + longevity-optimal ranges
What is a normal Testosterone level?
Testosterone is the primary male sex hormone, critical for muscle mass, bone density, mood, and energy. Normal range is 300-1000 ng/dL for men, 15-70 ng/dL for women. Levels decline ~1-2% per year after age 30. Importantly, visceral fat expresses the aromatase enzyme, which converts testosterone to estradiol — creating a negative feedback loop where obesity lowers testosterone, which promotes further fat accumulation. Standard labs do not age-adjust their ranges, so a 50-year-old is judged against the same curve as a 25-year-old. Longevity medicine targets 500+ ng/dL.
| Range | Values |
|---|---|
| Standard Reference | 300–1000 ng/dL |
| Optimal | 500–1000 ng/dL |
| Longevity Optimal | > 500 ng/dL |
| Low Risk | < 300 ng/dL |
What causes abnormal Testosterone levels?
Low testosterone is caused by aging (levels decline ~1-2% per year after 30), obesity and excess body fat, chronic stress and elevated cortisol, poor sleep (less than 7 hours), excessive alcohol, certain medications (opioids, statins), pituitary disorders, and testicular conditions. In women, low testosterone may cause reduced libido and fatigue.
When should you see a doctor?
See your doctor if your total testosterone is below 300 ng/dL (men) or if you have symptoms like persistent fatigue, low libido, erectile dysfunction, muscle loss, depression, or brain fog. Your doctor should also test free testosterone, SHBG, LH, and FSH to determine the underlying cause.
Testosterone and longevity
The aromatase enzyme pathway is central to understanding midlife testosterone decline. Visceral adipose tissue highly expresses aromatase, which actively converts circulating testosterone into estradiol. This creates a devastating negative feedback loop: low testosterone promotes fat accumulation, which further depletes testosterone reserves. Breaking this cycle through body recomposition (losing visceral fat, gaining lean mass) is the most effective natural intervention. SHBG (sex hormone-binding globulin) adds another layer of complexity — it binds testosterone, rendering it bio-unavailable. A high Total Testosterone with elevated SHBG can coexist with severe deficiency symptoms because Free Testosterone is extremely low. Standard diagnostic labs compound the problem by not age-adjusting reference ranges, meaning a 30-year-old and a 70-year-old are judged against the same statistical curve.
Where to get a Testosterone test
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Related biomarkers
These biomarkers are often tested alongside Testosterone for a more complete picture.
Frequently asked questions
What is a normal testosterone level?
What causes low testosterone?
What is the difference between free and total testosterone?
Can testosterone be raised naturally?
Why don't labs age-adjust testosterone ranges?
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Sources: Reference ranges based on AHA/ACC, ADA, and AACE clinical guidelines. Biological variation data from Ricos/Westgard database. Longevity-optimal ranges reflect targets used by preventive and functional medicine practitioners.
Last reviewed: April 2026. This tool provides general health information and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider about your specific results.