What is the average penis size?

In Veale et al. 2015, a systematic review of 17 studies with 15,521 men measured by health professionals: erect length 13.12 cm (5.2 in), erect girth 11.66 cm (4.6 in), flaccid length 9.16 cm and flaccid girth 9.31 cm. Self-reported surveys give higher numbers.

How rare is 9.5 cm girth?

About 1 in 40 men have an erect girth of this size or smaller, on a normal curve with mean 11.66 cm and SD 1.10. In inches that is 3.7 in.

Is 9.5 cm girth normal?

An erect girth of 9.5 cm (3.7 in) is larger than 2% of men, going by Veale et al. 2015, which pooled 15,521 men measured by health professionals: mean 11.66 cm, SD 1.10. That is 1 in 40 at this girth or smaller.

Percentile

of men have a smaller erect girth than 9.5 cm

9.5 cm girth = 3.7 in

Below averageBand by distance from the Veale 2015 mean, in standard deviations: within one SD is the middle two thirds of men. A description of the data, not a clinical category.

9.5 cm girth by group

Percentile

Normal curve, mean 11.66 cm, SD 1.10
Group	Mean	Smaller than you	1 in X
Men worldwide (Veale 2015)	11.66 cm	2%	1 in 40

The four measurements in Veale 2015

Means and standard deviations, 15,521 men measured by health professionals
Measurement	Mean	SD	Mean in inches
Erect length	13.12 cm	1.66	5.2 in
Erect girth	11.66 cm	1.10	4.6 in
Flaccid length	9.16 cm	1.57	3.6 in
Flaccid girth	9.31 cm	1.00	3.7 in

Percentile is the share of men with a smaller measurement. “1 in X” counts the rarer side: people at or beyond this value above the median, at or under it below. Percentiles are estimated from a normal distribution with Veale's mean and SD; regional rows use the regional mean with the same SD.

What this means

9.5 cm girth is 2.16 cm below the mean of 11.66 cm, 1.96 standard deviations. About 68% of men fall between 10.6 and 12.8 cm, and 95% between 9.5 and 13.9 cm.
Girth is the circumference of the shaft. Veale's erect girth mean is 11.66 cm (4.6 in), with a narrower spread than length: an SD of 1.10 cm against 1.66 for length.
Self-reported surveys come out higher than measured ones, usually by 1 to 2 cm: men round up, and men who are larger are more likely to answer. Veale et al. used only studies in which a health professional did the measuring, which is why these pages use that data and not survey figures.
Flaccid and erect sizes are different measurements. Veale's flaccid length mean is 9.16 cm (SD 1.57) against 13.12 erect, and flaccid size is a weak guide to erect size. These pages compare erect girth only.

Questions

Is 9.5 cm girth normal?: 9.5 cm erect girth is larger than 2% of men in Veale et al. 2015 (mean 11.66 cm, SD 1.10). That is below the mean by more than one standard deviation, though still within the range the pooled studies measured.
What is the average penis size?: In Veale et al. 2015, a systematic review of 17 studies with 15,521 men measured by health professionals: erect length 13.12 cm (5.2 in), erect girth 11.66 cm (4.6 in), flaccid length 9.16 cm and flaccid girth 9.31 cm. Self-reported surveys give higher numbers.
How rare is 9.5 cm girth?: About 1 in 40 men have an erect girth of this size or smaller, on a normal curve with mean 11.66 cm and SD 1.10. In inches that is 3.7 in.

Source: Veale et al., BJU International 2015, 115(6): systematic review of 17 studies, 15,521 men measured by health professionals. Erect length mean 13.12 cm, SD 1.66; erect girth mean 11.66 cm, SD 1.10. Regional means from Wylie and Eardley 2007, Herbenick et al. 2014 and Awwad et al. 2005, as used by our test. Percentiles are estimated from a normal distribution with Veale's mean and SD; regional rows use the regional mean with the same SD.

Erect or flaccid, length or girth, cm or inches: your percentile against Veale 2015.

Compare your measurements