Triangular Prism Surface Area Calculator

Calculate the surface area of a triangular prism by entering the triangle base, height, and prism length. A triangular prism has triangular bases and rectangular sides.

📐 Triangular Prism Surface Area

Formula

Surface Area: SA = 2 × Triangle Area + Perimeter × Length
Triangle Area: A = ½ × base × height
Where base and height are triangle dimensions, length is prism length

Triangular Prism Surface Area Formulas

Surface Area

SA = 2A + PL

Two triangular faces plus three rectangular faces

Triangle Area

A = ½bh

Area of each triangular base

Triangle Perimeter

P = a + b + c

Sum of all three triangle sides

Volume

V = A × L

Triangle area times prism length

Triangular Prism Surface Area Examples

Example 1: Right Triangle Prism

Given: Base = 3 cm, Height = 4 cm, Length = 10 cm

Triangle Area: A = ½ × 3 × 4 = 6 cm²

Hypotenuse: c = √(3² + 4²) = 5 cm

Perimeter: P = 3 + 4 + 5 = 12 cm

Surface Area: SA = 2 × 6 + 12 × 10 = 132 cm²

Example 2: Isosceles Triangle Prism

Given: Base = 6 cm, Height = 4 cm, Length = 8 cm

Triangle Area: A = ½ × 6 × 4 = 12 cm²

Side length: s = √(3² + 4²) = 5 cm

Perimeter: P = 6 + 5 + 5 = 16 cm

Surface Area: SA = 2 × 12 + 16 × 8 = 152 cm²

Example 3: Equilateral Triangle Prism

Given: Side = 6 cm, Length = 12 cm

Height: h = (√3/2) × 6 ≈ 5.196 cm

Triangle Area: A = ½ × 6 × 5.196 ≈ 15.59 cm²

Perimeter: P = 6 + 6 + 6 = 18 cm

Surface Area: SA = 2 × 15.59 + 18 × 12 ≈ 247.18 cm²

Triangular Prism Surface Area FAQ

What is a triangular prism?

A triangular prism is a 3D shape with two parallel triangular bases connected by three rectangular faces. Examples include tent shapes and roof structures.

How do you calculate triangular prism surface area?

Calculate the area of both triangular faces (2 × triangle area) and add the area of the three rectangular faces (perimeter × length).

What if I don't know all triangle sides?

For a right triangle, use the Pythagorean theorem (c = √(a² + b²)). For other triangles, you may need additional measurements or use trigonometry.

How do I find the triangle perimeter?

Add all three sides of the triangle. If you only know base and height, you'll need to calculate the other sides using geometry formulas.