Most People Will Go Their Entire Lives Without Ever Knowing Why Airplane Windows Are Round

If square windows were just as safe, airlines would likely still use them for their slightly larger viewing area.

Safety always comes first.

Why Airplane Windows Are So Small
Another question people often ask is why airplane windows are so small in the first place.

Again, pressure is the answer.

Smaller windows mean:

Less structural disruption

Lower stress on the fuselage

Reduced risk during decompression

Larger windows would require significantly heavier reinforcement, increasing weight and fuel costs.

Some newer aircraft, like the Boeing 787 Dreamliner, use electronically dimmable windows instead of physical shades—but the shape remains rounded, because the physics hasn’t changed.