Resistor Calculator
Calculate equivalent resistance for series or parallel resistors, estimate current and power, and decode resistor color bands or SMD markings.
Series and parallel resistor networks
English SERP intent expects a practical electronics calculator: enter resistor values, choose series or parallel wiring, and check the equivalent resistance plus current and power when a supply voltage is known.
Series resistors add directly.
Parallel resistors add by reciprocal conductance.
Power dissipation should be checked against the resistor package rating.
Color bands and SMD markings
The tool also covers common bench workflows: 4-band, 5-band and 6-band color codes, numeric SMD codes, R notation, zero-ohm jumpers and EIA-96 markings.
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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