Design a low-pass filter and calculate its response at any frequency.
A low-pass filter passes frequencies below cutoff and attenuates those above. At cutoff the output is 0.707 of input regardless of order, but the roll-off beyond it steepens with each additional stage. Anti-aliasing filters must attenuate everything above half the sampling rate, which usually requires third order or higher.
Low Pass Filter
Gain = 1 ÷ √(1 + (f/f_c)²) per order; f_c = 1 ÷ (2πRC)
Gain = 1 ÷ √(1 + (f/f_c)²) per order; f_c = 1 ÷ (2πRC) A low-pass filter passes frequencies below cutoff and attenuates those above. At cutoff the output is 0.707 of input regardless of order, but the roll-off beyond it steepens with each additional stage.
Anti-aliasing filters must attenuate everything above half the sampling rate, which usually requires third order or higher.
This calculator takes 4 inputs: Resistance, Capacitance, Signal frequency, Filter order. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.