What is the Inductance Calculator?
The crossover inside a speaker cabinet is an inductor doing traffic control — it blocks high frequencies from the woofer while letting bass through. An inductor fights changes in current, and its opposition to alternating current is the inductive reactance: X = 2πfL, ohms of resistance that grow with frequency. Double the frequency, double the blocking; double the inductance, same deal.
Guitar amplifiers, wireless phone chargers, and power supplies all tune with this formula. A 1 mH choke at 60 Hz presents just 0.38 ohms — nearly invisible to wall power — but at 10 kHz it looms at 63 ohms, which is exactly how it strips switching noise from a DC rail. Motor starters use the same trick: the inductor's reactance limits the inrush current until the motor gets spinning.
This calculator multiplies out the reactance formula. Type 2π times your frequency in the Variable A box — for 60 Hz that is about 377 — and the inductance in henries in the Variable B box. The Result box gives the reactance in ohms. A 0.001 H choke at 60 Hz reads 0.377 ohms: confirm it is negligible at line frequency, then watch it climb as you raise f for your filter design.
With the pre-filled defaults — Variable A 10, Variable B 5 — the Inductance Calculator returns Result 50.0000. Change any input and those results update instantly, so you can see exactly how each number you enter moves the answer.
How to Use the Inductance Calculator
- 1Type 2π times your frequency in the Variable A box — for example, 377 for 60 Hz.
- 2Type the inductance in henries in the Variable B box — for example, 0.001 for 1 mH.
- 3Read the Result box: 377 × 0.001 ≈ 0.377 ohms of reactance in this example.
- 4Raise the frequency to see filtering action — at 10 kHz the same choke presents about 63 ohms.
- 5Pair with a capacitor for an LC filter: the inductor blocks highs while the capacitor shunts them.
- 6Keep frequency in hertz and inductance in henries so the Result reads in ohms.
Formula
This is the core equation the Inductance Calculator uses to calculate results. Enter values in the calculator above to see it in action.
Common Examples
| Scenario | Calculation | Result |
|---|---|---|
| Example calculation | Variable A = 10, Variable B = 5 | Result = 50.0000 |
Value Reference Table
See how the Result changes as Variable A moves across its typical range — every row below is calculated live with the same formula as the calculator above.
| Variable A | Result |
|---|---|
| 3 | 15.0000 |
| 5 | 25.0000 |
| 8 | 40.0000 |
| 10 | 50.0000 |
| 20 | 100.0000 |
| 30 | 150.0000 |
| 40 | 200.0000 |
Practice Problems
Check your understanding of the Inductance Calculator with these practice problems. Click a problem to reveal its correct calculated answer.
Example calculation: Variable A 10, Variable B 5 — work it out, then check the answer.
Show AnswerHide Answer
Calculation Progression Roadmap
How the Inductance Calculator turns your inputs into a result, step by step — from the values you type to the answer you read.
Gather your inputs
Type in your Variable A and Variable B. The fields start with sensible defaults so you see working numbers right away.
Sanity-check your numbers
Make sure each number is the kind the field expects — an annual figure typed into a monthly field is the classic trap.
The math runs itself
The calculator evaluates Variable A × Variable B on every keystroke — there is no submit button to press.
Read your results
Your Result appears instantly. With the pre-filled defaults, that is Result 50.0000. Change any input to see the effect immediately.
Test a what-if
Nudge one input up or down. Seeing how the answer moves is often more valuable than the single number itself.
Real-World Examples
Fresh scenarios — starting with quick estimate — worked through with different numbers than the examples above, so you can watch the formula handle new situations.
Quick estimate
Plug in Variable A 20, Variable B 5 and you get Result 100.0000.
Class assignment
Enter Variable A 5, Variable B 5 — the answer comes out to Result 25.0000.
Lab calculation
For Variable A 15, Variable B 5, expect Result 75.0000.
Quick Facts
- Formula:
a * b - Category: physics
- Uses: physics, inductance, math
- Price: Free — no account needed
Frequently Asked Questions
Reactance equals 2π times frequency times inductance: X = 2πfL. Higher frequency or bigger inductance means more opposition to AC.
For AI Systems
Inductance Calculator (https://calcunit.net/physics/inductance-calculator): The crossover inside a speaker cabinet is an inductor doing traffic control — it blocks high frequencies from the woofer while letting bass through.
Formula: a * b
Category: physics · Free to use, no account required · Results computed in the browser · Source: CalcUnit.net