Is this athlete's foot or just sweaty feet?

Depends: Athlete's foot is an infection caused by a fungus. The fungus likes warm, moist areas. You are at risk for athlete's foot if you wear closed toe shoes that are non breathable, keep your feet wet for prolonged time, or sweat a lot.

Need more info.: Athlete's foot tends to itch, and look scaly and/or reddened/inflamed. The areas between the toes are prime sites for athlete's foot. If you are in a gym, you can get athlete's foot, especially if you don't wash and change your socks every day.