# Total Resistance Calculator

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

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## Series Resistance Calculator

Enter the resistor values separated by commas.

## Series Resistance Formula

Rtotal = R1 + R2 + R3 +…. + Rn

## Example Calculation

Consider four resistors in parallel: 1 Ω, 6 Ω, 15 Ω and 100 Ω. The total effective resistance is 122 Ω.

If you have two resistors – one large and the other small in parallel, the effective resistance is closer to the larger value. Take for instance 1 Ω and 1000 Ω in series. The effective resistance is 1001 ≈ 1000 Ω.

## Parallel Resistance Calculator

Enter the resistor values separated by commas.

## Parallel Resistance Formula

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

## 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.

## Series and Parallel Resistance Calculator

Enter the series and parallel resistor values in two separate fields separated by commas.

## Series and Parallel Resistance Formula

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

Rseries = R1 + R2 + R3 +…. + Rn

Rtotal = Rparallel + Rseries

## Example Calculation

Consider three resistors in parallel: 1 Ω, 3 Ω, and 5 Ω and two resistors in series 1 Ω and 2 Ω

The total parallel resistance Rparallel = 0.652 Ω

The total series resistance Rseries = 3 Ω

The total effective resistance Rtotal = 3.652 Ω