Inductance Calculator Formula

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

Use the Inductance Calculator

Formulas Used

Inductance

inductance = 4e-7 * pi * pow(turns, 2) * area / sol_length

Inductance (mH)

inductance_mh = 4e-7 * pi * pow(turns, 2) * area / sol_length * 1000

Variables

VariableDescriptionDefault
turnsNumber of Turns100
areaCross-Sectional Area(m²)0.001
sol_lengthSolenoid Length(m)0.1

How It Works

Solenoid Inductance

Inductance quantifies the ability of a coil to store energy in a magnetic field.

Formula

L = mu_0 * N² * A / l

where N is the number of turns, A is the cross-sectional area, and l is the solenoid length.

Worked Example

A solenoid with 100 turns, area 0.001 m², length 0.1 m.

turns = 100area = 0.001sol_length = 0.1
  1. 01L = mu_0 * N² * A / l
  2. 02L = 4*pi*1e-7 * 10000 * 0.001 / 0.1
  3. 03L = 1.2566e-3 * 0.01
  4. 04L = 1.2566e-5 H = 0.1257 mH

Ready to run the numbers?

Open Inductance Calculator