New Online Tool: Capacitive Reactance Calculator

11/13/2025

With this calculator, you can quickly calculate the capacitive reactance (Xc) of a capacitor for any given frequency and capacitance. Useful for students, professionals, and DIY enthusiasts. We also provide three simple examples of practical applications.

What is Capacitive Reactance?

Capacitive reactance (X_C) describes how a capacitor resists the flow of alternating current at a given frequency. The formula is:

X_C = 1 / 2πfC

where:

• f — frequency (in hertz, Hz);
• C — capacitance (in farads, F);
• X_C — capacitive reactance (in ohms, Ω).

This online calculator allows you to enter (f) and (C) and instantly get the value of (X_C) without manual math.

It's useful for:

• Students — when doing lab work or course projects;
• Engineers — in AC circuit analysis and design;
• DIY users — when working with audio systems, power supplies, or filters at home.

You can try it on the T&M Atlantic website: Capacitive Reactance Calculator.

Simple Examples of Application

Student Project: RC Circuit in Lab

• Data: C = 0.1 µF = 1.0×10^–7 F, f = 1 kHz = 1000 Hz
• Calculation: X_C = 1 / 2×π×1000×1.0×10^–7 ≈ 1591 Ω
• Result / Interpretation: the capacitor provides about 1.6 kΩ reactance at 1 kHz. Helps to choose resistor values and predict circuit behavior.

Professional Use: Audio Filter

• Data: C = 0.47 µF = 4.7×10^–7 F, f = 20 kHz = 20000 Hz
• Calculation: X_C = 1 / 2×π×20000×4.7×10^–7 ≈ 17 Ω
• Result / Interpretation: at high frequencies, the capacitor "passes" the signal (low reactance). Useful in audio crossover filters and coupling circuits.

Home / DIY: Power Supply Smoothing

• Data: C = 10 µF = 1.0×10^–5 F, f = 50 Hz
• Calculation: X_C = 1 / 2×π×50×1.0×10^–5 ≈ 318 Ω
• Result / Interpretation: in AC ripple filtering, reactance shows how effectively a capacitor smooths voltage after rectification.

Please visit our website for free and simple use of Multifunctional engineering calculations of electronic circuits and components.