Sock length

Is there a “rule of thumb” for estimating the sock length from heel to toe if I know the shoe size the person wears? These are “surprize” socks so I can’t ask him to measure his foot! Thanks all.
Susan in NC

Here’s a chart I found online:

I found this the other day when i was trying to figure out children’s sock sizes when I didn’t want to directly ask their mothers! :wink: it has heel flap legths and everything!

:muah: Thanks so much!

:blooby: ohh thanks I had been wondering about this if I decided to do some slipper socks for gifts…