Half a size smaller. I have US 10 and I ordered 10.5 which fits perfectly. Choose your size based on EU sizes. My size 10 shoes always have EU 44 on the tag, this size chart says 43 so they run small. I have a normal wide foot and it fits snugly but not too tight. The knobs are longer than I expected with a mix of thicker and heavier knobs in the traction areas. It's perfect because I use them on semi-compacted ground and tall grass. I'll post an update if they suck for this use. They fit like shoes and don't crumple under your foot like cleats.