How to use the Triangular Prism Surface Area Calculator
The Triangular Prism Surface Area Calculator works out your total surface area in an instant. Enter triangle side a, triangle side b and triangle side c and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
Enter the triangle side a.
Enter the triangle side b.
Enter the triangle side c.
Enter the prism length.
Read off your total surface area — the calculator updates automatically, with no button to press.
Formula
The Triangular Prism Surface Area Calculator uses the formula:
Total surface area = 2 × √((Triangle side a + Triangle side b + Triangle side c) ÷ 2 × ((Triangle side a + Triangle side b + Triangle side c) ÷ 2 - Triangle side a) × ((Triangle side a + Triangle side b + Triangle side c) ÷ 2 - Triangle side b) × ((Triangle side a + Triangle side b + Triangle side c) ÷ 2 - Triangle side c)) + (Triangle side a + Triangle side b + Triangle side c) × Prism length
Worked example
For example, with triangle side a of 3, triangle side b of 4, triangle side c of 5 and prism length of 10, the total surface area is 132.0000.
Inputs used
Triangle side a
3
Triangle side b
4
Triangle side c
5
Prism length
10
Results
Total surface area
132.0000
Results are estimates for educational use, not professional advice.
Key terms explained
Surface area
The total area of all the outer faces of a three-dimensional object.
Area
The amount of two-dimensional space a shape covers, measured in square units.
Frequently asked questions
Add the two triangular ends to the three rectangular sides: 2 × triangle area + perimeter × length. A 3-4-5 triangle, length 10, gives 132.
It uses Heron's formula from the three sides, so you do not need the triangle's height.
Each side of the triangle becomes a rectangle whose area is that side times the prism length.
No. Any valid triangle works, since Heron's formula handles all triangle shapes.
The Triangular Prism Surface Area Calculator uses the formula: Total surface area = 2 × √((Triangle side a + Triangle side b + Triangle side c) ÷ 2 × ((Triangle side a + Triangle side b + Triangle side c) ÷ 2 - Triangle side a) × ((Triangle side a + Triangle side b + Triangle side c) ÷ 2 - Triangle side b) × ((Triangle side a + Triangle side b + Triangle side c) ÷ 2 - Triangle side c)) + (Triangle side a + Triangle side b + Triangle side c) × Prism length. For example, with triangle side a of 3, triangle side b of 4, triangle side c of 5 and prism length of 10, the total surface area is 132.0000.
Enter the triangle side a. Enter the triangle side b. Enter the triangle side c. Enter the prism length. Read off your total surface area — the calculator updates automatically, with no button to press.
Reference table of total surface area for Triangular Prism Surface Area across a range of triangle side a values — exact, engine-computed figures you can read off at a glance.
Learn how to calculate Triangular Prism Surface Area — the formula explained step by step, with worked examples and a free calculator to check your answer.