Series Resistor Calculator

Determine the equivalent resistance of a series circuit with the series resistor calculator.

Total resistance1.69 kΩ3 components in series — they add directly

Number of components3

Sum of the values1.69 kΩwhich is the answer, in this arrangement

Smallest value220 Ω

Largest value1 kΩ

Component 1220 Ω13.02% of the total

Component 2470 Ω27.81% of the total

Component 31 kΩ59.17% of the total

In parallel instead130.3252 Ωthe same components, arranged the other way

Note for capacitorsthey combine the opposite waycapacitors add in parallel and combine reciprocally in series — the reverse of what you see here

The formula

series and parallel combination — capacitors work the opposite way

Capacitors are the exception

Resistors and inductors add in series and combine reciprocally in parallel. Capacitors do exactly the reverse: they add in parallel and combine reciprocally in series.

It is not arbitrary. What actually adds in series is always impedance, and a capacitor's impedance is inversely proportional to its capacitance. Adding impedances in series therefore means adding reciprocals of capacitance, which is where the apparent inversion comes from. Physically, putting capacitors in series is like making the dielectric thicker, which reduces capacitance; putting them in parallel is like making the plates bigger, which increases it.

Two useful consequences. Whenever reciprocals add, the total is always smaller than the smallest individual component, and n identical components give exactly one nth of a single value. That gives you a quick sanity check: a parallel resistance larger than any of its resistors is an arithmetic error.