Is it normal to sweat behind your knees?
Yep.Totally normal
Yes, it’s normal to sweat behind your knees. That area can get warm and a bit tucked away, especially when you’re exercising or it’s hot.
Your body sweats to cool itself down, and the skin behind your knees can trap warmth—particularly when your legs are bent, you’re moving around, or the weather’s warm. Lots of people notice sweat there, even if it’s not the first place they think of.