Free Online Tool
RC Time Constant Calculator
Calculate the RC time constant τ from resistor and capacitor values, including 1τ, 3τ, and 5τ times.
The result will appear here.
How to Use
- Enter resistance and capacitance with units.
- Click calculate.
- Review τ, 3τ, 5τ, and converted input values.
Examples
- Calculate time constant for 10kΩ and 100µF
- Check 5τ as a practical near-final settling time
Calculation and Conversion Notes
The RC time constant is calculated as `τ = R × C`. The tool also shows 1τ, 3τ, and 5τ. In general, 1τ corresponds to about 63.2% charged or about 36.8% discharged. 5τ is commonly used as a near-final settling time.
FAQ
Does RC Time Constant Calculator save my input?
No. Your input is not stored on a server. Supported actions run in your browser.
Can I use it on mobile?
Yes. The pages are responsive and work on desktop and mobile browsers.
Can I rely on the result?
Use the result as a quick reference. Important work should be checked separately.