The Earth is a three-dimensional sphere, meaning it has length, width, and height.

Here's a breakdown of the Earth's dimensions:

* Length and Width: These are roughly the same, as the Earth is close to a perfect sphere. The circumference of the Earth at the equator is approximately 40,075 kilometers (24,901 miles).

* Height: This refers to the distance from the Earth's surface to its center. The Earth's radius is approximately 6,371 kilometers (3,959 miles).

Therefore, the Earth's three dimensions are approximately:

* Length: 40,075 kilometers

* Width: 40,075 kilometers

* Height: 6,371 kilometers (radius)