Series & Parallel Resistor Calculator

Calculate combined resistance for series or parallel resistor networks.

Enter values for each resistor (leave blank to exclude).

Ω
Ω
Ω
Ω
Ω
Ω
Result
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Enter values for each resistor (leave blank to exclude).

Ω
Ω
Ω
Ω
Ω
Ω
Result
—

Formulas

  • Series: R_total = R1 + R2 + R3 + ...
  • Parallel: 1/R_total = 1/R1 + 1/R2 + 1/R3 + ...
  • Two parallel: R_total = (R1 × R2) / (R1 + R2)

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