Inductive Reactance Calculator
Enter a frequency and an inductance to find the inductive reactance Xl in ohms. Reactance is the opposition an inductor presents to alternating current, and it rises as either the frequency or the inductance increases.
How to use the inductive reactance calculator
- Enter the signal frequency in hertz (or kilohertz).
- Enter the inductance in henries (or millihenries, microhenries).
- Read the inductive reactance Xl in ohms.
Examples
10 mH at 1 kHz
f = 1000 Hz, L = 0.01 H
Xl = 62.83 ohm
0.1 H at mains 60 Hz
f = 60 Hz, L = 0.1 H
Xl = 37.70 ohm
Frequently asked questions
What is inductive reactance?
Inductive reactance Xl is the opposition an inductor offers to alternating current, measured in ohms. It is given by Xl = 2 pi f L.
Why does reactance rise with frequency?
Frequency multiplies the inductance in the formula, so doubling the frequency doubles the reactance. At high frequencies an inductor behaves more like an open circuit.
What is the reactance of a 10 mH inductor at 1 kHz?
About 62.83 ohms, from Xl = 2 pi * 1000 * 0.01.
How does inductive reactance differ from capacitive reactance?
Inductive reactance rises with frequency while capacitive reactance falls with frequency. The two cancel at the resonant frequency of an LC circuit.
Does the inductor resistance matter?
This tool gives ideal reactance only. Real inductors also have winding resistance, so the total impedance is the square root of R squared plus Xl squared.
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