Many men notice a significant difference between their flaccid and erect penis size. This is completely normal and is influenced by anatomy, blood flow, temperature, and individual physiology.
Understanding this difference is important, particularly for men considering penis enlargement surgery or penis filler treatments.
The flaccid penis is highly responsive to external factors, including:
Temperature
Stress and anxiety
Physical activity
Blood circulation
This is why flaccid size can change throughout the day. Cold environments and stress can cause the penis to retract, while warmth and relaxation can increase flaccid hang.
Some men are “growers,” meaning their flaccid penis is smaller but expands significantly when erect. Others are “showers,” with less variation between states.
Erect size is determined primarily by internal erectile tissue and blood flow. Unlike flaccid size, erect length and girth tend to remain consistent under similar conditions.
For this reason, urologists place greater emphasis on erect measurements when assessing anatomy and treatment suitability.
At Moorgate Andrology:
Flaccid measurements are taken before surgery or fillers
Post-operative comparisons focus on flaccid length and girth
Erect measurements may be discussed but are not always required
👉 Learn how measurements are taken:
https://knowledgebase.moorgateandrology.co.uk/measuring-your-penis-when-it-is-erect-length-girth
Penis enlargement surgery can increase:
Flaccid length (ligament release)
Permanent girth (fat transfer)
👉 https://moorgateandrology.co.uk/penis-enlargement-surgery/
Penis fillers increase:
Girth (temporary, 12–24 months)
Flaccid hang may appear improved due to reduced retraction
👉 https://moorgateandrology.co.uk/penis-fillers/
Erect length increase following surgery is usually modest, and fillers do not increase erect length.
Differences between flaccid and erect size are normal. If concerns persist, a medical consultation is the best way to determine whether treatment is appropriate or necessary.