Series & parallel resistance
Series & parallel resistance: use resistances in ohms, connection. Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
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Formula & explanation
Series R = ΣRᵢ; parallel R = 1/Σ(1/Rᵢ)
Variables & units
- Resistances in ohms
- comma separated
- Connection
- Select an option
Worked example
100 Ω and 200 Ω in parallel gives 66.666667 Ω.
Assumptions
Ideal positive resistors only; excludes tolerance, temperature, power ratings and impedance.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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