Electronics

Series & parallel resistors

Equivalent resistance of several resistors in series or parallel.

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ℹ️ Series: R = R₁ + R₂ + … Parallel: 1/R = 1/R₁ + 1/R₂ + … 100% local.

Compute equivalent resistance

Enter the values in ohms separated by commas, choose series or parallel: the result appears.

Example (100, 220, 330 Ω)

ConfigurationEquivalent resistance
Series650 Ω
Parallel≈ 56.9 Ω

Exact calculation. 100% local.

Frequently asked questions

Which formula in series?

Resistances add up: R = R₁ + R₂ + … The total is always larger than the largest one.

Which formula in parallel?

1/R = 1/R₁ + 1/R₂ + … The total is always smaller than the smallest one.

How many resistors?

As many as you like: separate the values with commas (e.g. 100, 220, 330).