FullCalculator

Capacitor Charge Calculator

Capacitor Charge

Calculate RC circuit charge time to a target level.

Formula

Time = -R x C x ln(1 - target%)

Frequently Asked Questions

What is a time constant?
Tau = R x C. It is the time to reach 63.2% charge.
How long to fully charge a capacitor?
About 5 time constants to reach 99.3% of full charge.