Low Pass Filter Calculator

Find the cutoff frequency of an RC low-pass filter.

Cutoff frequency (Hz) 1,591.55

Formula: fc = 1 ÷ (2π·R·C)

Step-by-step with your numbers:

1. Values used:

2. Resistance = 1,000 Ω

3. Capacitance = 0.1 µF

5. Cutoff frequency = 1,591.55Hz

Did we solve your problem today?

A low-pass filter passes low frequencies and attenuates high ones.

The math behind it

The −3 dB cutoff is fc = 1 ÷ (2π·R·C). Above it, output falls 20 dB per decade.

1 kΩ, 0.1 µF → about 1592 Hz.

Low-pass vs high-pass?

Swapping the resistor and capacitor positions turns one into the other.