Normal shoe size is 7.5 - 8, and I ordered the 7-8 size slipper. I have narrow, flat feet that these slippers fit perfectly. Enough wiggle room in the toe for comfort but the heel & opening are small enough that they stay on my foot snugly. The rubber sole is flexible enough that I can curl up in the chair without needing to remove the slippers. The overall padding plus a normal pair of socks is the right weight to keep my feet warm without making them sweaty The fur isn't super thick and fluffy like lambswool, but it's soft and comes just to the top of my ankles to keep them warm. It did shed a little bit for the first day or two of use. Overall, I recommend these to anyone looking for a good house slipper, especially with wood floors. But if you have thick ankles or wide feet, order up a size or look elsewhere.

UPDATE:
Owned these for two years, and they are still in excellent condition - no rips, tears, or holes; and only a little stretched out. I got a new pair of slippers for Christmas so I'll be retiring these, but they probably would have lasted another two years.