Parallel Resistance Calculator
Calculate the equivalent resistance of up to three resistors connected in parallel using the reciprocal formula 1/R = 1/R₁ + 1/R₂ + 1/R₃.
Formula: 1/R = 1/R₁ + 1/R₂ + 1/R₃
About Parallel Resistance Calculator
Parallel Resistance Calculator is a free online calculator that gives you an instant, accurate result as you type. Calculate the equivalent resistance of up to three resistors connected in parallel using the reciprocal formula 1/R = 1/R₁ + 1/R₂ + 1/R₃.
The calculation uses the standard formula 1/R = 1/R₁ + 1/R₂ + 1/R₃ and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
The equivalent resistance of a parallel combination is always smaller than the smallest individual resistor in the group.
Frequently Asked Questions
Is Parallel Resistance Calculator free to use?
Yes. Parallel Resistance Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (1/R = 1/R₁ + 1/R₂ + 1/R₃) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
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