RC Circuit Calculator (Time Constant & Cutoff)
RC time constant, low/high-pass cutoff frequency and charge times for a resistor–capacitor circuit.
How to use the RC Circuit Calculator
- Enter or select: Resistance R, Capacitance C.
- The results (Time constant τ, Cutoff frequency, Time to ~99.3% (5τ), Time to 50%) are calculated instantly as you type.
- Use “Copy link” to share the calculation with the same input values.
Formula
- τ = RC
- f_c = 1/(2πRC)
- V(t) = V₀(1 − e^(−t/τ))