Previous studies have found that men with longer, ultra-masculine ring fingers are likely to be more sporty, macho and aggressive. So the South Korean researchers wondered if finger ratio was also a giveaway for penis length.
They measured the penises of 144 men, and the measurements were later compared to the difference in length between their right-hand '2D' and '4D' - the second and fourth digits.
Sure enough, they found that more testosterone exposure in the womb makes for a longer penis as well as a longer ring finger. The lower the ‘2D:4D ratio’ between the two fingers, the longer a man’s penis is likely to be.
Work out your 2D:4D ratio
- Lay your right hand flat, palm up
- Measure your ring and index fingers from the tip to where they meet your palm
Index finger length divided by ring finger length equals 2D:4D ratio
- A lower ratio is more ‘masculine’
- Women are more likely to have a ratio of 1
- Men are more likely to have a ratio of less than 1