RC/RL passive filter calculator Posted by Ekostra Electronics July 8, 2026 On July 8, 2026 Ad EKOSTRA / TOOLS RC / RL Passive Filter Calculator Pick a topology, choose the value to solve for, fill in the other two — the result updates live. Filter response Low Pass High Pass Topology RC · Resistor–Capacitor RL · Resistor–Inductor Solve for Cutoff Frequency Resistance Capacitance Resistance (R) MΩ kΩ Ω Capacitance (C) −3 dB Cutoff Frequency GHz MHz kHz Hz Reset values Fill in the two highlighted fields Formulas Response curve (illustrative) Ad