Current Density Calculator Formula

Understand the math behind the current density calculator. Each variable explained with a worked example.

Formulas Used

Current Density

current_density = current / (area * 1e-6)

Current Density

current_density_amm2 = current / area

Variables

VariableDescriptionDefault
currentCurrent(A)10
areaCross-Sectional Area(mm²)2.5

How It Works

Current Density

Current density describes how much current flows through a unit area of a conductor.

Formula

J = I / A

where I is the current and A is the cross-sectional area of the conductor. High current density causes excessive heating.

Worked Example

10 A through a wire with 2.5 mm² cross-section.

current = 10area = 2.5
  1. 01J = I / A
  2. 02J = 10 / 2.5 mm²
  3. 03J = 4 A/mm²
  4. 04J = 4,000,000 A/m²

Ready to run the numbers?

Open Current Density Calculator