RC / RL / RLC calculator — time constant, cutoff, resonance & phase

Derive RC and RL time constants, evaluate gain and phase for two-element filters, and inspect series RLC resonance parameters with a live “How it’s calculated” log, CSV export, and shareable URLs.

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What this calculator covers

The RC / RL / RLC calculator unifies four workflows used in electronics labs and classroom demonstrations. Every computation pushes a detailed step-by-step trail so you can follow the algebra from formula to substituted numbers.

Step-by-step logging Each calculation writes the exact substitutions used so students can verify every transformation.
Share or export Persist inputs in the URL, copy links, and export CSV snapshots for lab notes.
Keyboard ready Press Enter to run, Ctrl+S for CSV, and Ctrl+L to copy the shareable URL.

Inputs

Results

How it’s calculated

    FAQ

    Can I reproduce the acceptance values from datasheets?
    Yes. Try RC low-pass with R = 1 kΩ, C = 100 nF, f = 1 kHz to confirm the magnitude 0.846733, gain −1.445070 dB, and phase −32.141908°.
    Does the RLC mode cover damping and bandwidth?
    Enter R = 20 Ω, L = 10 mH, C = 1 µF to see ω₀ = 10 000 rad/s, f₀ = 1591.549431 Hz, Q = 5, ζ = 0.1, and bandwidth 318.309886 Hz.

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