RC Capacitor Charging Calculator
Estimate capacitor voltage over time after a DC step from an initially discharged state.
Your result
EVERYDAYEnter your values and select calculate.
On this page How it works & practical examples
How to use the RC Capacitor Charging Calculator
Capacitance is entered in microfarads and converted to farads. The capacitor starts at zero volts and charges through the entered series resistance toward a constant DC voltage.
The calculation
Worked example
10 kΩ and 100 µF have a one-second time constant; after one second at 5 V, capacitor voltage is about 3.1606 V.
Assumptions and limits
Ideal first-order charging only; leakage, source resistance, initial charge and component tolerances are excluded. It does not assess component voltage or power ratings.
Common questions
Which inputs should I use?
Capacitance is entered in microfarads and converted to farads. The capacitor starts at zero volts and charges through the entered series resistance toward a constant DC voltage.
What does the result exclude?
Ideal first-order charging only; leakage, source resistance, initial charge and component tolerances are excluded. It does not assess component voltage or power ratings.