Triangular Prism Volume Calculator
A triangular prism is a three-dimensional solid with two parallel triangular bases connected by three rectangular faces. The volume is calculated by multiplying the area of the triangular base by the length (or depth) of the prism: V = (1/2) * b * h_t * l, where b is the base of the triangle, h_t is the perpendicular height of the triangle, and l is the length of the prism. The triangular base area is (1/2) * b * h_t. The surface area calculation requires the three sides of the triangle to compute the perimeter, which is then multiplied by the prism length to get the lateral surface area. The total surface area includes both triangular bases and all three rectangular faces. This calculator computes the volume and surface areas from the triangle dimensions (base and height) and the prism length.
Triangular prism volume formulas
Volume = (1/2) * b * h_t * l
Triangle Base Area = (1/2) * b * h_t
Triangle Perimeter = side1 + side2 + side3
Lateral Surface Area = Perimeter * l
Total Surface Area = (2 * Triangle Base Area) + Lateral Surface Area
Reference volumes
| Triangle Base | Triangle Height | Prism Length | Volume |
|---|---|---|---|
| 3 cm | 2 cm | 5 cm | 15.00 cm³ |
| 5 cm | 4 cm | 10 cm | 100.00 cm³ |
| 6 cm | 5 cm | 12 cm | 180.00 cm³ |
| 1 m | 1 m | 2 m | 1.00 m³ |
| 4 m | 3 m | 8 m | 48.00 m³ |
Triangular prism volume calculator: frequently asked questions
What is a triangular prism?
A triangular prism is a three-dimensional shape with two parallel triangular bases connected by three rectangular faces. It is named for its triangular cross-section. Examples include Toblerone bars, tent shapes, and roof structures.
What is the formula for triangular prism volume?
The volume is the area of the triangular base multiplied by the length (or height) of the prism: V = (1/2) * b * h_t * l, where b is the base of the triangle, h_t is the height of the triangle, and l is the length of the prism.
How do I calculate the area of the triangular base?
The area of a triangle is (1/2) * base * height. The height is the perpendicular distance from the base to the opposite vertex, not necessarily the length of a side.
What surfaces are included in total surface area?
The total surface area includes both triangular bases plus all three rectangular faces. The rectangular faces have dimensions that depend on the triangle sides and the prism length.
What are examples of triangular prisms?
Common triangular prisms include Toblerone candy bars, tent shapes, triangular roof structures, prism-shaped buildings, pencils (hexagonal are common, but triangular exist), and triangular tunnels.
Official sources
- Khan Academy: Volume and surface area of solids.
- NIST: National Institute of Standards and Technology.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.