Surface Area Calculator
Surface area is the total area of all the faces of a solid — the amount of paint, wrap or sheet material it takes to cover it.
Surface area of a solid
Formulas
| Solid | Total surface area |
|---|---|
| Cube | 6s² |
| Rectangular prism | 2(lw + lh + wh) |
| Cylinder | 2πr² + 2πrh |
| Sphere | 4πr² |
| Hemisphere (with base) | 3πr² |
| Cone | πr² + πr√(r² + h²) |
| Square pyramid | s² + 2s × slant height |
Worked example
Cylinder with radius 3 and height 5
- Two circular ends: 2 × π × 3² = 18π
- Curved side: 2 × π × 3 × 5 = 30π
- Total: 48π ≈ 150.8
Total surface area ≈ 150.8 square units; lateral area ≈ 94.25.
Lateral vs total
Lateral area leaves out the bases. For a cylindrical tank without a lid, or the label on a can, the lateral area (plus one base where relevant) is what you need.