This conversion is primarily for educational purposes to show the vast difference in scale between everyday measurements and cosmic distances, or in highly theoretical scientific contexts.

A light-year is the distance that light travels in a vacuum in one Julian year. It's a unit of astronomical distance.

There are an incredibly large number of inches in a light-year, roughly 3.72 x 10^20 inches. This makes a million inches a minuscule fraction of a light-year.

No, this specific conversion is not useful for everyday life. It's a theoretical comparison used to emphasize the immense distances in space.