R/C Filter

Passive Components Interactive calculator

Ideal first-order RC low-pass or high-pass filter using the standard cutoff formula.

Formula

fc = 1 / (2 x π x R1 x C1), τ = R1 x C1.

Compute cutoff frequency and response magnitude for RC filters.

Filter Type

Choose low-pass or high-pass.

Resistance Ω

Optional when solving from capacitance and cutoff.

Capacitance F

Unit-aware entry, e.g. 100nF, 1uF, 0.001F.

-3 dB Cutoff Frequency Hz

Optional target cutoff to compare against the calculated -3 dB cutoff.

All values are unit-aware and validated before computation.