Electrical & Electronics

RC Time Constant

Calculate RC time constant and inspect charging levels from 1τ to 5τ.

CALCULATOR

Enter values

R

C

USAGE

How to use it

Enter R and C with units.
Read time constant and settling table.
Inspect the charging curve.

FORMULA

Calculation

τ = RC; V(t)=V∞(1−e^(−t/RC))

Example

10 kΩ and 100 µF gives τ = 1 s

TECHNICAL

Technical notes

The table assumes an ideal source and capacitor.