Average Penis Girth: Erect Circumference in cm & Inches
The 2015 systematic review reported mean erect circumference of 11.66 cm (4.59 inches), based on 381 measurements. The overall review included 15,521 men across several measurement categories; not all participants provided erect measurements. Girth means circumference around the shaft, not width across.
Circumference vs diameter explained
Many men confuse girth (the distance all the way around the outside) with width across (diameter). When men refer to a 4.6-inch girth, they mean circumference. A penis with a 4.6-inch girth is about 1.46 inches wide.
What is considered thick or thin?
The reference mean for erect circumference is 11.66 cm (4.59 inches). A threshold for thick or thin depends on context; the calculator percentile is modelled from the mean and standard deviation, not a direct count.
Why girth matters more than length in bed
There is no single dimension that determines sexual pleasure or satisfaction. Preferences vary between individuals, and communication and mutual comfort matter.
My Size Report provides a private, calculator-led way to understand measurements against published research. Results are informational and should not be treated as medical advice.