Use this circuit calculation for ideal components under the stated series, parallel, or first-order RC model with compatible SI units.

Resistances (ohm)

Required list in ohm. Resistor values in ohms, each positive.

The cited overview of Electrical network supplies background for the terminology and domain context used by this tool.^[1]

Sum resistors wired in series: R_total = sum(R_i). Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Total resistance (ohm)

Returned number in ohm. Sum of all series resistances.

• Tolerance, temperature, frequency dependence, parasitics, leakage, source impedance, transients, and component ratings are outside an ideal lumped calculation unless explicitly supplied.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

Check component datasheets and tolerances, then validate consequential designs with circuit simulation and measurement under expected operating conditions.

• Parallel Resistance Calculator

  Combine resistors in parallel into one equivalent resistance via reciprocal summation.

• Electrical Current Calculator

  Calculate electrical current from voltage and resistance using Ohm's law.

• Electrical Resistance Calculator

  Calculate electrical resistance from voltage and current using Ohm's law.