Normally I am a 7.5-8, closer to 7.5.  I followed reviews and ordered a 7 and it fits like it's 1/2 too big.  So be conservative when ordering - you don't want them too big or they will be uncomfortable.  Bought them for OR work, standing long periods, and walking around.  They are perfect.  My feet don't hurt, and the cushion hasn't lost its firmness after approximately 36 hours of constant use.  Who knows after longer.  I'll edit the review it if it lasts a year I suppose but for the price, I would buy one every month if I needed to!