RC filter

How the calculation works

Calculate cutoff frequency of a simple RC low-pass or high-pass filter. The tool converts the form units and presents the result using readable engineering notation.

f꜀ = 1 / (2πRC)

Example

1 kΩ and 100 nF gives a cutoff near 1.59 kHz.

How to interpret the result

• Cutoff frequency is where amplitude falls to about 70.7% of the passband level.
• Source and load impedance can shift the real cutoff.
• A steeper response requires a higher-order or active filter.

Limitations and safe use

The result uses a simplified model. Check tolerance, temperature, absolute ratings and the component datasheet.