Inductive and Capacitive Reactance Calculator

Operating frequency: Hz,  Desired reactance value: Ohms
(eg: approx. 8 Ohms for first order crossover, 11.3 Ohms for second order crossover)

Required inductance L = mH,   Required capacitance C =

    

Operating frequency: Hz,  Inductance: mH

Reactance calculation results: XL = Ohms

    

Operating frequency: Hz,  Capacity:   

Reactance calculation results:XC = Ohms

    

An Inductive and Capacitive Reactance Calculator is a tool that helps you calculate the reactance (opposition to alternating current) presented by inductors and capacitors in an AC (alternating current) circuit. Reactance is similar to resistance but applies only to AC circuits, where inductors and capacitors oppose changes in current in different ways.

What is it?

  • Inductive Reactance (X_L): This is the opposition to current flow caused by an inductor in an AC circuit. It increases with the frequency of the AC signal.

    XL​ = 2πfL

    Where:

    • XL​ is the inductive reactance (in ohms),
    • f is the frequency (in hertz),
    • L is the inductance (in henrys).

  • Capacitive Reactance (X_C): This is the opposition to current flow caused by a capacitor in an AC circuit. It decreases with the frequency of the AC signal.

    Where:

    • XC​ is the capacitive reactance (in ohms),
    • f is the frequency (in hertz),
    • C is the capacitance (in farads).

Why is it important?

Reactance is a critical concept in AC circuits because it affects the phase and magnitude of the current relative to the voltage. Knowing the reactance helps you:

  • Understand how inductors and capacitors influence current flow.
  • Determine the total impedance of the circuit (combining resistance, inductive reactance, and capacitive reactance).
  • Design and troubleshoot filters, oscillators, and other AC systems.

How does it work?

You enter the frequency of the AC signal along with the inductance or capacitance values for the inductor or capacitor you're analyzing. The calculator then uses the formulas to compute the reactance.

For inductive reactance, it calculates based on the inductance value and frequency. For capacitive reactance, it calculates using the capacitance value and frequency. If both components are in the same circuit, the calculator can also help you find the total reactance or impedance (in a series or parallel configuration).

When is it used?

You would use this calculator when you need to calculate the reactance in circuits involving inductors and capacitors, such as:

  • In AC signal processing (filters, tuning circuits)
  • In impedance matching for maximum power transfer
  • In the design of reactive power compensation circuits
  • In analyzing the behavior of circuits with alternating current
  • In resonance circuits (like in radio receivers or transmitters)