Parallel Resistance
Combine ideal resistors sharing the same voltage.
Your numbers
Equivalent resistance
Idealized SI-unit educational model. Real components, tolerances, losses and safe operating limits require separate verification.
Scenario comparison
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Formula
Use Rₑ = 1/Σ(1/Rᵢ). Each Rᵢ is a positive parallel resistor value in Ω. Sum their reciprocals, then take the reciprocal again for equivalent resistance Rₑ.
Combine ideal resistors sharing the same voltage.
Worked example
- Resistor values (Ω)
- 10, 20
- Equivalent resistance
- 6.66666666667 Ω
Scope and limitations
Idealized SI-unit educational model. Real components, tolerances, losses and safe operating limits require separate verification.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: db2fa6a93e1f · Example checked: