What is the average erect penis length?

Yael Cooperman, MD - Contributor Avatar

Reviewed by Yael Cooperman, MD, Ro, 

Written by Health Guide Team 

Yael Cooperman, MD - Contributor Avatar

Reviewed by Yael Cooperman, MD, Ro, 

Written by Health Guide Team 

last updated: Dec 11, 2023

1 min read

Size is certainly not everything. That’s been proven again and again in research. But knowing whether your penis length is above or below average is something that occupies a lot of men’s minds. So what’s the average erect penis length? Read on to learn more. 

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What is the average length of an erect penis?

A study published in 2020 compared what people think is the average erect penis length to real numbers, and their findings might surprise you. They found that while most people assume the average length surpasses 6 inches, in reality, it’s a lot closer to 5 inches. Their meta-analysis, which compared participants from 31 different studies measuring penis length, showed that the average erect penis length hovers somewhere between 5.1-5.5 inches (though they suspect it’s at the lower end of that range). 

And you may be even more surprised to learn that while men typically overestimate average penis size, they are also more likely than their partners to be dissatisfied with their penis size. A study among heterosexual men and women showed that only 55% of men were happy with their penis size, while 85% of women were satisfied with their male partners’ penis sizes. 


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

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Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

December 11, 2023

Written by

Health Guide Team

Fact checked by

Yael Cooperman, MD

About the medical reviewer

Yael Cooperman is a physician and works as a Senior Manager, Medical Content & Education at Ro.