Do I need sunscreen near a window or on a cloudy day?

Clouds and windows do not eliminate UV exposure. If you spend time near a window, drive, or go outdoors, sun protection still matters. Sun protection should match actual daylight exposure and lifestyle rather than relying on whether the day looks bright.

Clouds and windows do not remove all UV exposure

A broad-spectrum SPF 30 or higher is a useful baseline, together with shade or protective clothing where practical.