Well - I'm not going out to the garage right now for a caliper and an accurate measurement, but tape measure says it's 1-1/8" from the outside face of the crankarm to the flat part of my '07 Keo Classic. No idea how that compares to other pedals. Look pedals are known for a large contact surface, so they're supposedly good for not causing hot spots.
I've never ridden anything but Look-compatible pedals (since toe clips). When I got my new bike I tried Eggbeaters, but I just could not get out of them even in the shop on the trainer, so I went back to the Look style pedals I knew from back in the day.
HTH...