Understanding Testosterone Levels: What’s Considered Normal by Age?

Nico Bryant-Aguilar

— 3 min read

Testosterone is a vital hormone that plays a crucial role in muscle growth, bone density, energy levels, and overall well-being. As men and women age, testosterone levels naturally fluctuate, sometimes leading to symptoms of deficiency or imbalance.

In this article, we’ll explore normal testosterone levels by age, the factors that influence these levels, and when testing is necessary.

What Is Testosterone?

Testosterone is an androgen (male sex hormone) primarily produced in the testicles (in men) and in smaller amounts in the ovaries (in women). The adrenal glands also contribute to testosterone production.

In men, testosterone is essential for:
✅ Muscle and bone mass maintenance
✅ Libido and reproductive function
✅ Red blood cell production
✅ Mood and cognitive function

In women, testosterone supports:
✅ Bone strength
✅ Muscle maintenance
✅ Libido and mood regulation

Normal Testosterone Levels by Age

Testosterone levels are measured in nanograms per deciliter (ng/dL) in blood tests. Below is a general reference chart based on The Endocrine Society and Mayo Clinic data [¹][²].

Normal Total Testosterone Levels (ng/dL) by Age

Age RangeMen (ng/dL)Women (ng/dL)
0-5 years<12<12
6-10 years<25<25
11-15 years100-50015-40
16-19 years300-1,00020-75
20-29 years300-1,00015-70
30-39 years270-95015-60
40-49 years250-90015-50
50-59 years230-85015-45
60+ years200-75010-40

Free Testosterone Levels (pg/mL)

Free testosterone (the unbound, active form) is also measured in picograms per milliliter (pg/mL).

  • Men: 5–25 pg/mL
  • Women: 0.5–4.0 pg/mL

Free testosterone levels naturally decline with age, impacting energy, mood, and libido.

Why Do Testosterone Levels Decline With Age?

Testosterone production peaks in the late teens and early 20s, then gradually declines at a rate of about 1% per year after age 30 [³]. This process, often referred to as andropause (male menopause), is influenced by:

  • Aging: Natural decline in testicular function.
  • Increased Body Fat: More fat tissue leads to higher estrogen conversion.
  • Chronic Stress & Poor Sleep: Elevated cortisol levels suppress testosterone production.
  • Medical Conditions: Diabetes, obesity, and metabolic syndrome can accelerate decline.

When Should You Get Your Testosterone Levels Tested?

A testosterone blood test is recommended if you experience symptoms of low T, such as:

  • Men:
    ✅ Low libido or erectile dysfunction
    ✅ Chronic fatigue
    ✅ Decreased muscle mass
    ✅ Depression or mood swings
  • Women:
    ✅ Fatigue and low energy
    ✅ Low sex drive
    ✅ Weight gain or muscle loss

A total testosterone test is usually the first step, but doctors may also check free testosterone, SHBG (sex hormone-binding globulin), and DHT (dihydrotestosterone) for a full picture.

How to Maintain Healthy Testosterone Levels

While some testosterone decline is natural, lifestyle changes can help maintain optimal levels:

✅ Exercise & Strength Training

  • Resistance training (weightlifting) boosts testosterone levels naturally [⁴].
  • High-intensity interval training (HIIT) also shows positive effects.

✅ Get Enough Sleep

  • 7-9 hours of quality sleep is essential for testosterone production.
  • Deep sleep stages (REM & slow-wave sleep) are when most testosterone is produced.

✅ Eat a Balanced Diet

  • Healthy fats (avocados, nuts, olive oil) support hormone production.
  • Protein & carbs help regulate cortisol, which can lower testosterone.

✅ Manage Stress

  • Chronic stress increases cortisol, which suppresses testosterone levels.
  • Meditation, deep breathing, and exercise help regulate stress hormones.

✅ Consider Medical Treatment if Necessary

If testosterone levels are clinically low and causing severe symptoms, testosterone replacement therapy (TRT) may be an option. However, it should only be done under medical supervision.

Final Thoughts

Testosterone levels naturally fluctuate with age, but severe drops can indicate underlying health issues. If you suspect low testosterone, getting tested is the first step toward finding a solution.

For the most accurate measurement, a blood test is the best option. You can also check out our guide on How to Prepare for a Testosterone Test for tips on getting the best results.

Footnotes & Citations

  1. The Endocrine Society. “Testosterone Therapy in Men with Hypogonadism.” The Journal of Clinical Endocrinology & Metabolism, 2018. Available here
  2. Mayo Clinic. “Testosterone tests: Normal ranges and what they measure.” Mayo Clinic, 2022. Available here
  3. American Urological Association. “Evaluation and Management of Testosterone Deficiency.” AUA Guidelines, 2018. Available here
  4. Kraemer, W.J., et al. “Resistance Training Effects on Testosterone and Hormonal Response.” Journal of Strength & Conditioning Research, 2021. Available here

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