Inductive Reactance Calculator
Enter frequency and inductance to compute the inductive reactance X_L = 2π·f·L.
Input Data
Results
At a glance:Inductive reactance X_L is the opposition an inductor presents to alternating current: X_L = ω·L = 2π·f·L, where ω = 2πf is angular frequency and L the inductance (henries). It is the imaginary part of impedance (Z = R + jX_L). Unlike resistance, reactance stores and returns energy each cycle rather than dissipating it. X_L grows with frequency, so inductors block high frequencies and pass low ones (the opposite of capacitors). For DC (f=0) X_L = 0 — an ideal inductor is a short circuit. The current lags voltage by 90° in a pure inductor.
Formula
X_L = 2π·f·L = ω·L
$$X_L = 2\pi f L$$How to Use
- Enter the frequency f (Hz).
- Enter the inductance L (H).
- The calculator returns X_L.
Case Studies
Choke at 60 Hz
f = 60 Hz, L = 0.1 H.
X_L = 2π×60×0.1 ≈ 37.7 Ω.
Limits AC current while passing DC.
FAQ
Why does reactance increase with frequency?
A faster-changing current induces a larger back-EMF (Faraday's law), so the inductor opposes AC more strongly at high f. At f→∞ X_L→∞ (open); at f=0 it is a short.
Is reactance the same as resistance?
Both are in ohms, but resistance dissipates power (P=I²R) while reactance stores/releases energy; they combine as impedance Z = √(R² + X_L²). Power in pure reactance averages to zero.
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References
Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.