Testosterone Levels in Men by Age

Testosterone is the hormone at the core of male vitality, impacting everything from energy and strength to mood, libido, and cognitive function. Yet as men age, testosterone levels naturally decline—often starting as early as age 30. But age alone doesn’t tell the full story.

This guide breaks down what healthy testosterone levels look like by decade, when to be concerned, and why relying solely on lab numbers may leave many men underdiagnosed and untreated.

What Testosterone Does in the Male Body

Testosterone is produced primarily in the testes and is essential for a range of physiological functions, including:

• Sexual desire and performance

• Sperm production

• Hair growth

• Muscle strength and mass

• Bone density

• Mood and emotional regulation

• Cognitive clarity and focus

• Development during puberty

When testosterone falls below optimal levels, it can lead to symptoms like low libido, fatigue, irritability, poor concentration, and loss of muscle tone. These signs are often brushed off as “normal aging”—but they may actually signal low testosterone (Low T).

What Is a Normal Testosterone Level?

Medical opinions vary widely, but most laboratories define normal total testosterone levels as falling between 300 ng/dL and 1050 ng/dL. However, these numbers don’t tell the whole story.

A man can have a result of 300 ng/dL and still suffer from clear symptoms of Low T. That’s why relying only on lab results can be misleading. A qualified hormone replacement therapy (HRT) specialist will look beyond numbers—considering symptoms, medical history, and overall health—to make a proper diagnosis.

Why Age Matters, But Isn’t Everything

While age is a key factor in testosterone decline, lifestyle, stress levels, body composition, medications, and underlying health conditions can also cause dips in hormone levels.

Here’s a breakdown of average testosterone levels by age:

Men in Their 30s

• Free: 8.7 – 25.1 pg/mL

• Total: 219 – 1009 ng/dL

• Optimal range: 600 – 675 ng/dL

Men in Their 40s

• Free: 6.8 – 21.5 pg/mL

• Total: 201 – 993 ng/dL

• Optimal range: 500 – 550 ng/dL

Men in Their 50s

• Free: 7.2 – 24.0 pg/mL

• Total: 170 – 918 ng/dL

• Optimal range: 400 – 450 ng/dL

Men 60 and Above

• Free: 6.6 – 18.1 pg/mL

• Total: 156 – 700 ng/dL

• Optimal range: 300 – 350 ng/dL

Studies show that many men over 60 fall below 241 ng/dL—a level associated with fatigue, cognitive decline, and loss of muscle and motivation.

Testing and Monitoring

A total testosterone test is a simple blood test used to measure your levels. It’s most accurate when performed early in the morning, when testosterone naturally peaks. Because levels fluctuate throughout the day, some men may require a repeat test for confirmation.

For men over 35, routine monitoring every five years is advised. If symptoms of Low T appear, testing should happen sooner. And once treatment begins, regular check-ins are critical to ensure testosterone remains in a healthy and balanced range.

Bottom Line

Low testosterone is more common than most men think—and it often goes untreated due to outdated diagnostic standards. The key is not just identifying a number, but assessing the whole person. With proper monitoring, guidance, and if needed, therapy, men can reclaim energy, focus, libido, and physical performance.

If you’re experiencing symptoms or just want to optimize your health as you age, working with a hormone specialist is the first step.