ENGINEERING / FREE ONLINE TOOL
RC Time Constant Calculator
Find τ, settling times, and the RC cutoff frequency.
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Your result
A little guidance.
Calculate τ = R × C for an ideal first-order RC network. A charging response reaches about 63.2% after one time constant, 90% after ln(10)τ, and 99% after ln(100)τ. The associated cutoff is 1 / (2πτ).
How it works
- Enter your values, or use the example to get started.
- Select “Calculate” to process your input in your browser.
- Review the result, then copy or download it when available.
Good to know.
Is my input sent to a server?
No. This tool runs in your browser. KILIZU does not upload or store the values or files you enter here.