Does it count to get sunlight through a window?

No—not nearly as well as getting outdoors. Light through a window is estimated to be about 50 times less effective for circadian benefits, and setting the circadian clock through a window may take 50–100 times longer. Glass filters and scatters relevant wavelengths of light, especially when sunlight is not coming directly through the window. 1 2 3

Even on cloudy or overcast days, going outside can provide beneficial light; the guidance is to spend longer outdoors when it’s cloudy rather than relying on a window. 4