Series Resistor Calculator
Calculate total resistance, voltage drops and power dissipation for resistors connected in series.
Units: k or kohm, M or Mohm, G or Gohm. Use decimal ohms for very small values.
Power warnings above 0.25 W are only a small-resistor reference; verify the actual part rating.
Total resistance in series
Series resistor intent is straightforward: add each resistor value and, when voltage is supplied, calculate the common current and voltage drop across each part.
Series resistance is the sum of all resistor values.
Each voltage drop is proportional to that resistor's value.
Voltage dividers and power
Series resistors are often used as voltage dividers, current limiters and value-building combinations, but each package still needs a power check.
Frequently Asked Questions
Sources and References
- Conversion Calculator Parallel and Series ResistorDigiKey
- Parallel Resistor CalculatorAll About Circuits
- Resistor Color Code CalculatorMouser
- 21.1 Resistors in Series and ParallelOpenStax
Calculations are based on the listed reference sources. Links open in a new tab.
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