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Parallel Resistance Calculator (any number of resistors)

This calculator determines the total effective resistance of any number of resistors in parallel.

Enter the resistor values separated by commas.

Parallel Resistance Formula

Rtotal = (1/R1 + 1/R2 + 1/R3 +…. + 1/Rn)-1

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Example Calculation

Consider four resistors in parallel: 1 Ω, 6 Ω, 15 Ω and 100 Ω. The total effective resistance is 0.80 Ω.

If you have two resistors – one large and the other small in parallel, the effective resistance is closer to the smaller value. Take for instance 1 Ω and 100 Ω in parallel. The effective resistance is 0.99 ≈ 1 Ω.

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