Series and parallel resistors

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Calculate the equivalent resistance of multiple connected resistors in series or parallel. Add up to 12 values. Accept values with suffix: 1k, 4.7k, 10M, 100.

Resistors

Practical rules

Series

Resistances add up. Two 1 kΩ resistors in series make 2 kΩ. Miracle: a simple thing.

Parallel

The equivalent value is always smaller than the smallest resistor. Two equal resistors in parallel are worth half.

Format

Accepts 4k7, 2.2k, 1M, 100. Useful when copying values from real patterns.

Frequently asked questions

How to calculate resistors in series?

R_total = R1 + R2 + R3. Values simply add.

How to calculate resistors in parallel?

1/R_total = 1/R1 + 1/R2. Two equal: R_total = R/2.