Testosterone and Age

Testosterone Levels

Testosterone levels are measured in Nanograms per deciliter (ng/dl). A Nanogram is a very small amount. There are 1000000 Nanograms in 1 milligram. There are 1000 milligrams in a gram. There are 1000 grams in a kilogram and there are 2.2 pounds in a kilogram hence a Nanogram is less than 36 trillionths of an ounce!  
   
A deciliter is one-tenth of a liter. Hence a deciliter is about 3.814 fluid ounces.  
   
Here are some testosterone levels in healthy males. 



  
    Age   
    Testosterone Level (ng/dl)   
  
  
    0-5 months   
    75-400   
  
  
    6 months-9 years   
    7-20   
  
  
    12years-13years   
    7-800   
  
  
    14years   
    7-1200   
  
  
    17years-18years   
    300-1200   
  
  
    25years   
    270-1070   
  
  
    35years   
    257-1017   
  
  
    40years   
    243-963   
  
  
    50years   
    216-856   
  
  
    70years   
    162-642   
  


   
There are a few points that need to be emphasized:  
(i) At any age, there is a great range of testosterone levels that are regarded as 'normal'.  
(ii) Testosterone levels are high in the first few months of life.  
(iii) Testosterone levels are low until sometime from about 11 years old until 15 years when puberty sets in.  
(iv)  During the late teenage years, testosterone levels are the highest most men ever experience.  
(v) From ages 20 years - 30 years testosterone levels are pretty constant in the range 270 - 1070.  
(vi) After age 30 there is approximately a 1% decrease per year. ![](https://cdn.steemitimages.com/DQmTfALjTjBek7hboMFpKBaXskmWajbShFk2HaES9WbpJ9j/image.png)