Flaccid pendulous length averages 9.16 cm across 10,704 men. Stretched flaccid length averages 13.24 cm across 14,160 men. Erect length averages 13.12 cm across 692 men. Flaccid circumference averages 9.31 cm across 9,407 men. Erect circumference averages 11.66 cm across 381 men. Penis length strongly correlates with height at r=0.2 to 0.6. Few erect measurements done clinically. Greatest variability occurs in flaccid stretched length. Measurements by health professionals using standard procedures. Excluded men with penile abnormalities, surgery, or complaints of small size. Nomograms simulated from 20,000 normal distribution observations.