From https://doi.org/10.1371/journal.pone.0133079

So, yes, size matter (in preferences also).

• Just over 20% of women prefer a penis that is thicker than 99% of penises. (same for one-night partners)
• The upper 50% of women prefer a thickness that is thicker than ~70% of penises. (over 80% of penises for one-night partners)
• Just over 25% of women prefer a penis that is longer than 99% of penises. (same for one-night partners)
• The upper 50% of women prefer a length that is longer than ~90% of penises. (same for one-night partners)

Btw

According to one study on rats, penis length appears to be affected by fetal exposure to testosterone in utero. There’s a critical window in gestation where the more testosterone the fetus gets, the larger the penis. Outside of this window, testosterone does not have an effect on size.

https://webarchive.nationalarchives.gov.uk/20200923124103/https://mrc.ukri.org/news/browse/penis-length-is-determined-early-in-fetal-development/