Capacitor Charge Time Calculator
Calculate the RC time constant and charge/discharge curve of a capacitor through a resistor, including voltage over time, time to reach a target level, and a visual curve.
RC Parameters
Calculated Values
Voltage Curve
v(t) = Vmax × (1 − e^(−t/τ))5τ is practically considered fully charged (≈ 99.3%).
τ Milestones
| Multiple | Time | Charged |
|---|
How does this tool work?
Interactive RC calculator with charge/discharge curve, time constant τ = R·C, and time to reach any target voltage percentage.
Calculates the time constant τ = R × C, the voltage curve for charging v(t) = Vmax·(1 − e^(−t/τ)) and discharging v(t) = V0·e^(−t/τ), the time to reach a target voltage percentage, and the classic 1τ bis 5τ milestones (5τ ≈ 99.3% charged).
Where are my data processed?
Only in your browser. Your data is not sent to any server.
The tool calculates and converts with JavaScript right on your device. Input and files are not sent to us or anyone else. You can check this yourself: load the page, disconnect from the internet, and the tool keeps working in the open tab.