This is how you can actually know it.

Dailystar reports that Research conducted at Gachon University Gil Hospital in South Korea found that guys with a smaller difference in length between their two fingers – which is also known as the 24:4D ratio – were more likely to have bigger p*nis.
 
So what this means is that the shorter a man’s index finger was in relation to his ring finger, the longer his erect p*nis is likely to be.
 
Scientists aren’t exactly sure why there’s a correlation, but they think it has something to do with the hormones we’re exposed to in the womb.
 
On the other hand, some rumoured links between your fingers and your penis size aren’t so factual.
 
It’s long since been said that the distance between your thumb and index finger – when you hold your hand in an L-shape – is the same as the length of your p*nis.
 
However, there is no scientific evidence to back this up at all.
 
What your feet REALLY say about your p*nis size
 
Lots of people think you can tell how big a guy’s penis is by looking at other parts of his body, like his hands or feet. Urban legend says that a man’s todger is roughly half as big as the size of his shoe, so it’s not surprising that scientists have delved into the matter.
 
Researchers in the UK measured the size of 104 lads’ shoes and p*nises to tested out the theory and see if it really stands up.
To make sure the results were as accurate as possible, doctors did the measuring so men wouldn’t overestimate how much they were packing downstairs.
 
They noted down the length of each guy’s flaccid penis when it was fully stretched to give an indication of how big their joysticks were when erect. Scientists found that shoe sizes ranged from 5.5 to 13 while schlong lengths were between 2.4 inches and 7.1 inches.

Does the size of a man penis really matter to a woman?I only hear them complain of quick cum.

Wow