Why are planets spherical in shape?

If one weren't, it would collapse to a sphere under its own gravity. All the matter tries to fall toward the center, and will if there's nothing in its way. The sphere is the shape in which everything has fallen toward the center as far as it can. Actually, planets bulge out a little at their equators, because of their rotation. So they're not exactly spherical, but pretty close.

I think that planets are round because of the force of gravity. All of the planets spin and have a gravitational pull thus it would make sense that they become round because of the equal gravatational pull on all sides. Have a great day!!!