Surface Area of a Rectangular Prism Calculator

Calculate total surface area, lateral area, and volume of rectangular prisms with step-by-step solutions

Calculate Rectangular Prism Properties

First base edge length

Second base edge length

Lateral edge length (prism height)

Rectangular Prism Formulas

Base Area: A_b = l × w

Lateral Area: A_l = 2(lh + wh) = 2h(l + w)

Total Surface Area: A = 2A_b + A_l = 2lw + 2lh + 2wh

Volume: V = l × w × h

Space Diagonal: d = √(l² + w² + h²)

Please enter valid positive values for all required fields

Example Calculations

Example 1: Shipping Box

Given: l = 8 ft, w = 6 ft, h = 5 ft

Base area: 8 × 6 = 48 ft²

Lateral area: 2(8×5 + 6×5) = 140 ft²

Total area: 2×48 + 140 = 236 ft²

Example 2: Swimming Pool

Given: l = 10 m, w = 4 m, h = 2 m

Base area: 10 × 4 = 40 m²

Lateral area: 2(10×2 + 4×2) = 56 m²

Total area: 2×40 + 56 = 136 m²

Quick Reference

Key Formulas

A = 2lw + 2lh + 2wh

A_l = 2h(l + w)

V = lwh

d = √(l² + w² + h²)

Components

6 rectangular faces

2 bases (top & bottom)

4 lateral faces

12 edges, 8 vertices

Rectangular Prism Facts

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3D Shape: Has length, width, and height (3 dimensions)
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Six Faces: All faces are rectangles
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Right Angles: All angles are 90 degrees
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Opposite Faces: Three pairs of identical rectangles

Quick Tips

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Also called a cuboid or rectangular box

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Total surface area includes all 6 faces

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Lateral area excludes top and bottom faces

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Space diagonal connects opposite vertices

Understanding Rectangular Prism Surface Area

What is a Rectangular Prism?

A rectangular prism (also called a cuboid) is a 3D shape with six rectangular faces. Think of a shoebox, shipping container, or any rectangular box. All angles are right angles (90°), and opposite faces are identical rectangles.

Surface Area Components

The surface area consists of all six faces: two identical bases (top and bottom) and four lateral faces. The lateral faces form the "sides" of the prism.

Formula Derivation

Step 1: Base Areas

Two bases: 2 × (l × w) = 2lw

Step 2: Lateral Areas

Four sides: 2(lh) + 2(wh) = 2h(l + w)

Step 3: Total Area

A = 2lw + 2lh + 2wh

Real-World Applications

Construction:

Calculate material needed for walls, floors, and ceilings of rectangular rooms

Packaging:

Determine wrapping paper or paint needed for boxes and containers

Swimming Pools:

Calculate tiling area for rectangular pools (excluding top surface)