Series Resistance Calculator
Ideal resistors connected in series add to give the total resistance of the chain.
How to use this calculator
- Enter two required resistor values and optionally a third or fourth value.
- Check the labels and units before using a result outside this page.
- Change one input at a time if you want to compare scenarios.
Formula and method
Rtotal = R₁ + R₂ + … + Rₙ
- Rtotal = R₁ + R₂ + … + Rₙ
- Component tolerance, temperature effects, power ratings and circuit safety are outside this arithmetic tool.
Worked examples
Worked example
Resistors 100 Ω, 220 Ω and 330 Ω are connected in series.
Total resistance = 100 + 220 + 330 = 650 Ω.
Total resistance = 100 + 220 + 330 = 650 Ω.
Understanding the result
Ideal resistors connected in series add to give the total resistance of the chain.
Component tolerance, temperature effects, power ratings and circuit safety are outside this arithmetic tool.
Important notes
Component tolerance, temperature effects, power ratings and circuit safety are outside this arithmetic tool.
Displayed outputs are rounded for readability; preserve full precision when continuing a calculation.
Frequently asked questions
What does this series resistance calculator show?
Ideal resistors connected in series add to give the total resistance of the chain.
Which inputs should I check first?
Enter two required resistor values and optionally a third or fourth value.
Can the result be used as a final professional specification?
Component tolerance, temperature effects, power ratings and circuit safety are outside this arithmetic tool.
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Related explanations
Learn the method behind the number or compare the terminology before using the calculator.
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This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.