Cross-Sectional Area Calculator

Calculate cross-sectional areas for beams, tubes, and geometric shapes used in engineering

Calculate Cross-Sectional Area

A solid circular cross-section

Diameter of the circular cross-section

Cross-Sectional Area Results

Formula Used

A = π × D² / 4
78.540 mm²
Cross-Sectional Area
78.54
mm²
0.7854
cm²
0.000079
0.1217
in²
0.000845
ft²

Example Calculation

Tube Cross-Section Example

Shape: Hollow circular tube

Outer diameter (D): 10 mm

Wall thickness (t): 1 mm

Inner diameter: D - 2t = 10 - 2(1) = 8 mm

Calculation Steps

A = π × (D² - (D - 2t)²) / 4

A = π × (10² - (10 - 2×1)²) / 4

A = π × (100 - 64) / 4

A = π × 36 / 4 = 28.274 mm²

Common Beam Shapes

I

I-Beam

Used in railway tracks

High strength-to-weight ratio

T

T-Beam

Bridge construction

Floor reinforcement

C

C-Beam

Channel sections

Structural framing

L

L-Beam

Angle brackets

Corner reinforcement

Quick Formulas

Circle

A = π × D² / 4

Rectangle

A = W × H

Tube

A = π × (D² - d²) / 4

I-Beam

A = 2Wt₁ + (H-2t₁)t₂

Understanding Cross-Sectional Area

What is Cross-Sectional Area?

A cross-section is the intersection of a 3D object with a plane. The cross-sectional area is the area of this intersection, which is crucial for determining the structural properties of beams, pipes, and other engineering components.

Why is it Important?

  • Determines load-bearing capacity of structures
  • Critical for stress and strain calculations
  • Essential for material quantity estimation
  • Required for flow calculations in pipes

Engineering Applications

Structural Engineering

Beam design, load calculations, building frameworks

Mechanical Engineering

Shaft design, stress analysis, material selection

Civil Engineering

Bridge design, concrete reinforcement, foundation planning

Fluid Mechanics

Pipe flow, pressure drop calculations, hydraulic systems