Human penis size is the measured length and width of the human penis. The most accurate measurement of the human penis comes from several measurements at different times, as there is natural variability in size due to arousal level, time of day, room temperature, frequency of sexual activity, and unreliability of the measurement methods. When compared to other primates, including large primates such as the gorilla, the genitalia of male humans are large, both in absolute terms and in relative size to the rest of the body. Results vary, with studies that rely on self-measurement reporting a significantly higher average than those with staff measuring, but a mean erect human penis is approximately 12...