Why is parallel resistance always lower than either resistor?

Adding a parallel path always gives current more ways to flow, which reduces total resistance below the smallest individual resistor.

Resistor Series & Parallel Calculator

Calculate the equivalent resistance of two resistors connected in series (resistances add) or in parallel (using the reciprocal formula).

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Formula

Series: R = R1+R2, Parallel: R = (R1×R2)/(R1+R2)

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