Here's a breakdown:

* Crust: The outermost layer of the Earth, ranging from about 3-5 miles (5-8 km) thick under the oceans (oceanic crust) to 25 miles (40 km) thick under the continents (continental crust).

* Mantle: The layer beneath the crust, extending about 1800 miles (2900 km) down to the Earth's core.

Therefore, the mantle is significantly thicker than the crust.