Impedance Calculator

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Introduction

Impedance Calculator — RLC series impedance from R, XL and Xc. Enter Resistance R (Ω), Inductive reactance XL (Ω), Capacitive reactance Xc (Ω) to get an instant, accurate result.

Formula

For a series RLC circuit, impedance is calculated as Z = √(R² + (X_L − Xc)²), where R is resistance, X_L is inductive reactance, and Xc is capacitive reactance.

Step-by-step

Enter the Resistance R (Ω).
Enter the Inductive reactance XL (Ω).
Enter the Capacitive reactance Xc (Ω).
Click Calculate to see your result instantly.

Real-world example

Example: With Resistance R (Ω) = 10, Inductive reactance XL (Ω) = 5, Capacitive reactance Xc (Ω) = 3, the Impedance Calculator gives Impedance Ohm: 10.198.

Frequently Asked Questions

What is impedance?

Impedance is the total opposition a circuit presents to alternating current, combining both resistance (energy dissipation) and reactance (energy storage in capacitors/inductors) into a single quantity, measured in ohms (Ω).

Why is impedance calculated using a square root of sums of squares?

Resistance and net reactance act as perpendicular components in the complex plane, so they combine like the legs of a right triangle (a form of the Pythagorean theorem) to give total impedance magnitude.

What does it mean when inductive and capacitive reactance are equal?

When X_L equals Xc, they cancel out, leaving impedance equal to just the resistance (Z = R) — this condition is called resonance in an RLC circuit.

What inputs does the Impedance Calculator need?

You'll need to provide: Resistance R (Ω), Inductive reactance XL (Ω), Capacitive reactance Xc (Ω). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.

How accurate is the Impedance Calculator?

The Impedance Calculator applies the formula exactly as calculated — For a series RLC circuit, impedance is calculated as Z = √(R² + (X_L − Xc)²), where R is resistance, X_L is inductive reactance, and Xc is capacitive reactance. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.

Is the Impedance Calculator free to use?

Yes, the Impedance Calculator is completely free, requires no signup, and runs instantly in your browser.

About the Impedance Calculator

The Impedance Calculator uses a real, verifiable formula — For a series RLC circuit, impedance is calculated as Z = √(R² + (X_L − Xc)²), where R is resistance, X_L is inductive reactance, and Xc is capacitive reactance. — so results are accurate every time, not an approximation.

Amortization schedule

Growth over time