Resistors in Parallel Calculator

Calculate the equivalent resistance (Req) of up to 4 resistors connected in a parallel branch.

Enter resistor values (Ω) to calculate equivalent parallel resistance

Equivalent Parallel Resistance:
Equivalent Req (Ohms): 0.000 Ω
In Kilohms (kΩ): 0.000 kΩ
Total Conductance (G): 0.000 S

How to Use

  • Enter at least two resistor values in Ohms (Ω).
  • Add up to 4 parallel resistor branches.
  • Click CALCULATE to compute the equivalent resistance and total conductance.

Parallel Circuit Rule

• The equivalent resistance is always smaller than the smallest individual resistor in parallel.

• The voltage drop across every parallel branch is identical: V_total = V1 = V2 = V3.

Parallel Resistor Formula

The reciprocal of the equivalent resistance equals the sum of reciprocals:

1 / Req = (1 / R1) + (1 / R2) + … + (1 / Rn)

For two resistors in parallel, the formula simplifies to the Product-Over-Sum rule:
R_eq = (R1 × R2) / (R1 + R2)

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