Slow RC Time Constant: 1MΩ and 1µF
A 1MΩ resistor and 1µF capacitor create an RC time constant of exactly 1 second, useful for long delay circuits.
How to use this tool
- Enter resistance (r) and capacitance (c) in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your time constant τ (s) and the full breakdown beneath it.
Large resistance values create long time constants — a 1MΩ and 1µF pair gives a clean 1-second RC time constant.
Frequently asked questions
- What is the time constant used for?
- The time constant tells you how fast an RC circuit responds. In filters it sets the -3 dB frequency; in timing circuits it controls pulse width.
- How do I convert nF or pF to µF?
- 1 µF = 1000 nF = 1,000,000 pF. A 100 nF cap = 0.1 µF; a 10 pF cap = 0.00001 µF.