The RC time constant tells you how fast a capacitor charges or discharges through a resistor, and it is the backbone of timers, filters and debounce circuits. This calculator multiplies your resistance in ohms by your capacitance in farads to give tau, the time constant in seconds. One time constant is the time to reach about 63 percent of the final voltage, and after five time constants the capacitor is considered fully charged or discharged at over 99 percent. The tool also gives you the cutoff frequency of the resulting low pass filter, which is one over two pi R C, so you can see how the same components behave in the frequency domain. Enter your R and C values, choosing convenient units like kilohms and microfarads, and the results update instantly. Everything runs locally in your browser.
The RC time constant tells you how fast a capacitor charges or discharges through a resistor, and it is the backbone of timers, filters and debounce circuits. This calculator multiplies your resistance in ohms by your capacitance in farads to give tau, the time constant in seconds.
Yes. RC Time Constant Calculator is completely free, with no sign-up and no usage limits.
Yes. RC Time Constant Calculator runs in any modern web browser. There is nothing to download or install.
Yes. RC Time Constant Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.