Prism Volume Calculator Formula

Understand the math behind the prism volume calculator. Each variable explained with a worked example.

Formulas Used

Volume

volume = l * w * h

Surface Area

surface_area = 2 * (l * w + l * h + w * h)

Diagonal

diagonal = sqrt(pow(l, 2) + pow(w, 2) + pow(h, 2))

Variables

VariableDescriptionDefault
lLength10
wWidth5
hHeight3

How It Works

Rectangular Prism (Box) Formulas

Volume

V = l × w × h

Surface Area

SA = 2(lw + lh + wh)

Space Diagonal

d = sqrt(l² + w² + h²)

The space diagonal runs from one corner to the opposite corner through the interior of the box.

Worked Example

Box with length 10, width 5, height 3.

l = 10w = 5h = 3
  1. 01Volume = 10 × 5 × 3 = 150
  2. 02Surface area = 2(50 + 30 + 15) = 2 × 95 = 190
  3. 03Diagonal = √(100+25+9) = √134 ≈ 11.5758

Frequently Asked Questions

What is a prism?

A prism is a 3D shape with two parallel, identical bases connected by rectangular faces. A rectangular prism (box) is the most common type.

Is a cube a prism?

Yes, a cube is a special rectangular prism where all three dimensions are equal.

What is the space diagonal?

The space diagonal is the longest line segment inside the box, connecting opposite corners through the interior. It uses a 3D version of the Pythagorean theorem.

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Open Prism Volume Calculator