R C Filter Calculator

Use this free r c filter calculator to calculate the cutoff frequency and time constant of an RC filter.

How the r c filter calculator works

Cutoff frequency f꜀ = 1 ÷ (2πRC). Time constant τ = R × C.

Frequently asked questions

What does the cutoff frequency mean?

It is where the output has fallen to about 70.7% (−3 dB) of the input in a first-order low-pass or high-pass filter.

Results are estimates for general information only. They are not a substitute for professional advice where applicable. Found a mistake? Report an error.