How to use the Triangle / Triangular Prism Cubic Feet Calculator
- Treat the end face as a triangle. Its height meets the base at a right angle; prism length runs between the matching triangular ends.
- Choose the shape mode, where available, and a unit for each dimension. Enter the number of identical objects.
- Select Calculate. Review the result and its working; if you change an input, calculate again before copying or sharing.
Triangle / Triangular Prism formula
Convert each length to feet, apply the displayed solid-volume formula, then multiply by the number of identical objects.
base × triangle height × length ÷ 2
What the terms mean
- Triangle base
- A measured length in the selected unit; it is converted to feet before volume is calculated.
- Perpendicular triangle height
- A measured length in the selected unit; it is converted to feet before volume is calculated.
- Prism length
- A measured length in the selected unit; it is converted to feet before volume is calculated.
- Number of identical items
- The whole-number count of objects with the same entered dimensions.
Triangle / Triangular Prism worked examples
Measure a triangular prism
A prism has a triangular cross-section with a 3 ft base and 4 ft perpendicular height, extending for 10 ft.
- base × perpendicular triangle height × length ÷ 2
- base = 3 ft
- triangleHeight = 4 ft
- length = 10 ft
- 60 ft³ × 1 = 60 ft³
Answer: 60 ft³. Cubic yards: 2.222222 yd³; Litres: 1,699.010796 L.
Estimate a wedge-shaped section
A triangular section has a 6 ft base, 2 ft perpendicular height and 4 ft prism length.
- base × perpendicular triangle height × length ÷ 2
- base = 6 ft
- triangleHeight = 2 ft
- length = 4 ft
- 24 ft³ × 1 = 24 ft³
Answer: 24 ft³. Cubic yards: 0.888889 yd³; Litres: 679.604318 L.
Triangle / Triangular Prism Cubic Feet Calculator FAQs
Is this suitable for a ramp?
Yes, when the side section is a triangle and the ramp has a constant width. Use the ramp width as prism length.
Is triangle height the sloping edge?
No. Use the perpendicular height. A sloping edge generally gives the wrong area.
Measurement guide for Triangle / Triangular Prism
The triangle height must be perpendicular to its base. The prism length is the distance between the two triangular ends.
Assumptions and limits
A flat triangle has area, not volume. This calculator assumes the triangular cross-section stays constant along the prism.
Check your result
Check the dimensions converted to feet in the working. For similar solids, doubling every dimension increases volume by a factor of eight.