I would say from 6' to 6' 6" to be a good range. I'm 6'6" and these fit great. i've had them for 9 months and after many washes there is no shrinkage. Hard to find long legged long john's, they fit better then any I've had before. The legs stay down whether I tuck under or over socks and stay there all day whether sitting, standing or working out in the construction field. Just moved to upstate New York from California so I will be getting a couple more of the mid-weight and heavyweights for the winter here.
Glad I found these. Great buy!