Size Percentile Calculator

What is the average penis size?

According to the Veale et al. (2015) BJU International meta-analysis of 15,521 men — the most-cited peer-reviewed study on this topic — the average measurements are:

• Erect length: 13.12 cm (5.17 inches), SD ±1.66 cm
• Flaccid length: 9.16 cm (3.61 inches), SD ±1.57 cm
• Erect circumference: 11.66 cm (4.59 inches), SD ±1.1 cm

How is the percentile calculated?

We assume a normal distribution based on the mean and standard deviation reported in the Veale et al. (2015) meta-analysis. Your percentile is the estimated percentage of men whose measurement is less than yours — calculated via the standard normal cumulative distribution function.

What is considered average?

In statistics, "average" is typically defined as within one standard deviation of the mean — covering roughly 68% of the population. For erect length, that is approximately 11.5 cm to 14.8 cm (or about 11.5-14.8 cm). Anything in this range is statistically typical.

Does size matter?

Multiple peer-reviewed studies find that size is not the primary factor in sexual satisfaction for most partners. Confidence, communication, and technique are consistently rated as more important. The anxiety around "being enough" is typically larger than any practical difference.

Where does this data come from?

Veale et al. (2015). BJU International, 115(6), 978-986. This is a systematic review and meta-analysis of 17 studies involving 15,521 men, using standardized measurement protocols (self-report was excluded from the nomogram data). It is the most rigorous and most-cited source available for this type of calculator.