Flaccid vs Erect Penis Size: Averages, Growth & What Matters
Flaccid size can change with temperature, stress, activity and other conditions, so a single resting measurement is not a reliable way to estimate erect length. Research has found that the relationship between flaccid and erect measurements varies between individuals. Compare measurements taken consistently, and treat population averages as context rather than a prediction about your body.
Why flaccid size does not predict erect size
Flaccid appearance varies between people and can change from one situation to another. A resting measurement alone does not tell you exactly how much length you will gain when erect; if comparing the two, use a consistent method and conditions.
Average flaccid length and thickness
Flaccid measurements are particularly sensitive to temperature, stress and recent activity. If you compare your own measurements over time, take them under similar conditions and avoid interpreting a single measurement as a health assessment.
Does flaccid size matter during sex?
Flaccid size alone does not determine sexual function or satisfaction. Individual anatomy, preferences and circumstances vary; a resting measurement is not a useful proxy for a partner’s experience.
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.