TheCircuitDogCircuit Fundamentals
Series and Parallel Resistor Calculator
Enter resistor values in ohms, separated by commas or spaces, and select a series or parallel connection.
Enter the values above and select Calculate result.
Formula
Rseries = ΣRi; 1 / Rparallel = Σ(1 / Ri)
Worked example
Three resistors of 1 kΩ, 2 kΩ and 3 kΩ in series total 6 kΩ. Their parallel combination is approximately 545.5 Ω.
Engineering notes
All values must be in ohms. Real resistors have tolerance, temperature coefficient and power-rating limits.
Always compare calculated values with the actual component datasheet, tolerance stack-up, operating temperature and circuit conditions before applying them to hardware.