EngineeringToolkit

RC Time Constant (Electrical) Formula

The time required to charge or discharge a capacitor through a resistor to about 63% of its final value.

Formula

τ = RC

Discipline: Electrical. Result unit: s.

Variables and units

  • τ — Time Constant (s): Time constant
  • R — Resistance (Ω): Resistance
  • C — Capacitance (F): Capacitance