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Calculate and design
RC low-pass filter
Choose a cutoff frequency and resistor. Calculate the capacitor, select standard values and open a circuit ready for AC simulation.
From calculation to circuit
Enter your inputs and calculate to see selected components, achieved results and editable circuit source.
How this calculation works
C = 1 / (2π × R × cutoff frequency)Nominal R/C values, ideal voltage source and high-impedance output. Extra source resistance, output loading and component tolerances are not included.
Use the same tool locally
Use Kessetsu CLI 1.1.0 or newer. Add --format json for an AI agent. Install or update the CLI.
kess tool rc-lowpass --cutoff "1kHz" --resistance "1k" --values e24 --output rc-lowpass.kess