〜 Filter Calculator

Low-Pass · High-Pass · Band-Pass · Band-Stop | RC · RL · LC topologies · Live Bode Plot

RC Low-Pass Filter

fc = 1 / (2πRC)

Resistance R (Ω)

Capacitance C

C Unit

Cutoff f_c

—

Angular ω_c

—

Time Constant τ

—

Gain at f_c

−3.01 dB

Test Frequency

Gain at f_test

—

Attenuation

—

f_c = 1 / (2π × R × C) | τ = RC
At f_c: gain = 1/√2 = 0.707 = −3.01 dB
Roll-off: −20 dB/decade (1st order RC/RL)

— Magnitude — −3 dB point — f_c

RC Low-Pass: Passes low frequencies, attenuates high frequencies above f_c. Used for noise filtering, audio treble cut, anti-aliasing before ADC.