Passive Filter Calculator

A filter is a circuit that is designed to pass signals with desired frequencies and reject or attenuate others. Given the value of the resistor and capacitor, our tool calculates the cut-off frequency of a series RC passive filter.

Low Pass Filter

A Low Pass Filter only allows low frequency signals from 0Hz to its cut-off frequency, ƒc point to pass while blocking those any higher.

Please enter your values below.

Formulas

fc = 1/2𝜋RCθ = −arctan(2𝜋fRC)

Diagram View

Low Pass Filter

High Pass Filter

A High Pass Filter only allows high frequency signals from its cut-off frequency, fc point and higher to infinity to pass through while blocking those any lower.

Please enter your values below.

Formulas

fc = 1/2𝜋RCθ = arctan(1/(2𝜋fRC))

Diagram View

High Pass Filter

Band Pass Filter

Passive Band Pass Filters allows signals falling within a certain frequency band setup between two points to pass through while blocking both the lower and higher frequencies either side of this frequency band.

Please enter your values below.

Formulas

flow = 1/2𝜋R1C1fhigh = 1/2𝜋R2C2

Diagram View

Band Pass Filter