RC Low-Pass Cutoff
A first-order RC low-pass cutoff is the frequency where amplitude falls to one over the square root of two.
RC Low-Pass Cutoff
Filters · 2 inputs
How to use this calculator
- Enter resistance in kΩ.
- Enter capacitance in nF.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Check the component connections and unit prefixes before copying a result into a circuit notebook. These tools describe ideal, introductory circuits. They do not replace datasheets, thermal checks, isolation requirements or qualified design work, and they are not intended for mains installation decisions.
Source impedance and output loading can shift the realized cutoff.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.
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