Inductor Energy Calculator
Energy stored in an inductor's magnetic field.
Enter your values
Enter the inductance in mH.
Enter the current in A.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Stored energy
- 200 mJ
- Stored energy
- 2.000e-1 J
- Inductance
- 100 mH
Quick answer
Energy E = 0.5 x L x I^2.
E = 0.5 L I^2
At a glance
| What it does | Energy stored in an inductor's magnetic field. |
|---|---|
| Category | Engineering |
| Inputs needed | Inductance, Current |
| Main output | Stored energy |
| Formula | E = 0.5 L I^2 |
| Cost | Free — no sign-up, no download |
How to use the Inductor Energy Calculator
- 1Enter the inductor's inductance in millihenries.
- 2Enter the current flowing through it.
- 3Read the energy stored in its magnetic field.
Inputs explained
- Inductance(mH)
- Enter the inductance in mH.
- Current(A)
- Enter the current in A.
Worked example
Using the values the calculator loads with:
Inputs
- Inductance100 mH
- Current2 A
Results
- Stored energy200 mJ
- Stored energy2.000e-1 J
- Inductance100 mH
Frequently asked questions
Why do inductors cause voltage spikes when switched off?
Collapsing the magnetic field induces a large voltage trying to maintain current flow — hence flyback diodes.
How does this compare to capacitor energy?
Both store energy but in different forms (magnetic vs electric field); formulas mirror each other.
What do I need to enter into the Inductor Energy Calculator?
Just 2 values: inductance, current. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Inductor Energy Calculator work out the answer?
Energy E = 0.5 x L x I^2. It applies the formula E = 0.5 L I^2 and shows the working so you can check each step by hand.
Is the Inductor Energy Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.