RC time constant
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Formula
τ = R·C
Worked example
Given: Resistance = 10 kΩ; Capacitance = 100 µF
Result: τ = 1 s; Cut-off frequency = 0.1592 Hz
How it is calculated
1. Enter the values you know. 2. The calculator converts them to base units and applies the formula. 3. The result is shown in the unit you choose.
Frequently asked questions
How do I calculate it?
Formula: τ = R·C. Given: Resistance = 10 kΩ; Capacitance = 100 µF. Result: τ = 1 s; Cut-off frequency = 0.1592 Hz.
Is the calculator free and private?
Yes. It is free, needs no sign-up and runs in your browser — the numbers you type stay on your device.