Physics

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Inductor Energy Calculator.

Calculate energy stored in an inductor's magnetic field.

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Energy: 0.2

Energy

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Educational SI models with assumptions stated in each description; verify engineering decisions independently.

Use Cases

Designing power supplies and converters

Engineers use inductor energy calculations to size inductors in switching power supplies, ensuring they store enough energy for proper operation.

Example: Calculate the energy stored in a 10 mH inductor with 2 A current.

Educational demonstrations in physics

Students and teachers can quickly compute the magnetic field energy for experiments or homework problems involving inductors.

Example: Find the energy in a 5 H inductor with 0.5 A current.

Frequently Asked Questions

How is the energy stored in an inductor calculated?
The energy (E) stored in an inductor is calculated using the formula E = 0.5 * L * I^2, where L is the inductance in henries (H) and I is the current in amperes (A). This calculator uses that formula to give you the energy in joules.
What units are used for inductance and current in this calculator?
Inductance is entered in henries (H) and current in amperes (A). The result is the energy stored in the magnetic field, expressed in joules (J).
Can this calculator be used for any type of inductor?
Yes, as long as you know the inductance value and the current flowing through it, you can calculate the energy stored. It applies to ideal inductors, assuming no losses.

Tips & Common Mistakes

Tips

  • Ensure inductance is in henries (H) and current in amperes (A) for accurate results. Convert millihenries or microhenries to henries first.
  • Remember that energy scales with the square of the current, so doubling the current quadruples the stored energy.
  • For real inductors, consider core losses and resistance, but this calculator assumes ideal conditions.
  • Use the result to compare energy storage capabilities of different inductors in your circuit design.

Common Mistakes to Avoid

  • Forgetting to convert units: entering inductance in millihenries (mH) without converting to henries (H) leads to incorrect energy values.
  • Using peak current instead of RMS current in AC circuits, which can overestimate the stored energy.
  • Assuming the energy is in millijoules when the calculator outputs joules, leading to misinterpretation.

Last updated: August 13, 2026