What Is the Average Penis Size?
Published studies provide useful benchmarks, but their estimates differ because they use different study populations and methods. The figures below distinguish the overall review sample from the smaller samples measured when erect.
2015 systematic review
Veale and colleagues reported mean erect length of 13.12 cm (5.16 inches), based on 692 measurements, and mean erect circumference of 11.66 cm (4.59 inches), based on 381 measurements. The review included 15,521 men across all measurement categories, not 15,521 erect measurements.
2025 review
A 2025 review reported mean erect length of 13.84 cm (5.45 inches) from 5,669 measurements and mean erect circumference of 11.91 cm (4.69 inches) from 5,168 measurements. Its overall review sample was larger than the samples contributing to these particular measurements.
Why studies differ
Results can vary with participant selection, measurement protocols and the studies included. These averages are useful reference points, not a universal threshold for normality or an exact prediction for an individual.
Compare your own measurements
Measure consistently, then use the calculator to compare length and girth separately. The calculator estimates percentiles from its stated reference distribution; it does not generate a new percentile model from the 2025 averages.
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.