Parallel Resistor Calculator
Calculate equivalent resistance for multiple parallel resistors.
Equivalent resistance
Complete every resistor to calculate.
Formula and method
1 / Req = 1/R1 + 1/R2 + …
Important assumptions
The equivalent is always lower than the smallest individual resistance.
Frequently asked questions
Does the calculation run locally?
Yes. Values are processed in your browser and are not sent to a server.
Can I use it for a real installation?
Use it as an educational reference and verify components, tolerances, safety, and applicable code with technical documentation or a qualified person.
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