Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Resistance (ohm)

Required number input.

Capacitance (F)

Required number input.

Supply voltage (V)

Required number input.

Target voltage (V)

Required number input.

Calculate RC charging time to a target voltage. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Time (s)

The resulting time returned as a number.

• Capacitance, ESR, leakage, ripple rating, lifetime, and self-resonance vary with frequency, temperature, DC bias, aging, dielectric, package, and mounting. Nominal capacitance alone does not determine in-circuit impedance or reliability.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• RC Charging Voltage

  Compute the charging voltage across an RC network after a given elapsed time.

• RC Discharging Voltage

  Compute the remaining voltage across a discharging RC network after a given elapsed time.

• Supercapacitor RC Time Constant

  Calculate τ=RC for a supercapacitor and a series or load resistance. This ideal first-order time constant does not model voltage-dependent capacitance or leakage.