Hemisphere Calculator
Calculate the volume, curved surface area, base area, total surface area, and circumference of a hemisphere from its radius.
Frequently Asked Questions
How do you calculate the volume of a hemisphere?
V = (2/3)πr³ — exactly half the volume of a sphere ((4/3)πr³). For a radius of 5: V = (2/3) × π × 125 ≈ 261.8 cubic units.
What is the surface area of a hemisphere?
The curved (dome) surface is 2πr² — half a sphere's surface. A solid hemisphere also has a flat circular base of πr², so the total surface area is 2πr² + πr² = 3πr². For r = 5: total SA = 3π × 25 ≈ 235.6 square units.
Is a hemisphere half of a sphere in surface area too?
Only the curved part. Half a sphere's surface is 2πr², but cutting a sphere in half exposes a new flat circular face (πr²) that the sphere never had — so a solid hemisphere's total surface (3πr²) is 75% of the full sphere's (4πr²), not 50%.
Where are hemisphere calculations used?
Domes in architecture (calculating material for a dome roof), tank and bowl capacity (hemispherical tank ends), astronomy and geography (Earth's hemispheres), lighting design (hemispherical diffusers), and cooking (hemispherical molds and bowls).