What are normal testosterone levels in men?

This is challenging question because men’s testosterone levels can vary depending on a man’s age, the time of day, and even the lab processing a blood sample.  In general, a total testosterone range of 300 to 1,000 ng/dL is considered normal, according to the Endocrine Society. The American Urological Association also uses 300 ng/dL as its cutoff point for diagnosing low testosterone (hypogonadism). Click through this slideshow to learn more about factors that influence testosterone measurement.