MihsabaHow to use
A triangular prism has two congruent triangular bases joined by three rectangular faces. Using all three triangle sides plus prism length lets the calculator solve area and surface quantities without assuming a right or isosceles triangle.
- Enter triangle sides a, b and c in the same unit.
- Enter prism length L, perpendicular to the triangular bases.
- The calculator validates the triangle inequality and uses a numerically stable Heron formula.
- Review base area, lateral area, volume and total surface area.
How it is calculated
Example
Example: a 3-4-5 base with prism length 10 has base area 6, volume 60, lateral area 120 and total surface area 132.
Important notes
Use the same length unit for every input. Areas are returned in squared units and volume in cubed units. Degenerate or impossible triangle sides are rejected.
Frequently asked questions
Why is triangle height not required?
Three sides determine triangle area through Heron’s formula and also determine perimeter, which is enough for volume and lateral area.
Does it work for right triangles?
Yes, and for any valid non-degenerate triangle.
Prism length versus triangle height?
Prism length is the distance between the triangular bases, not an altitude inside the triangle.
Is this calculator free?
Yes. It is free to use and requires no account.