What is the formula for resistors in parallel?

The reciprocal of the total equals the sum of the reciprocals — 1/Rt = 1/R1 + 1/R2 + ... + 1/Rn. The total is always smaller than the smallest individual resistor.

Can I enter more than two resistors?

Yes. Enter as many resistor values as you like, separated by commas or spaces, and the calculator sums all their reciprocals.

Is anything uploaded?

No — every calculation happens locally in your browser, with no network requests.

Parallel Resistance Calculator

Total resistance of resistors wired in parallel.

Parallel resistance calculator

When resistors are connected in parallel, the total (equivalent) resistance is found from the reciprocal rule:

1/R_t = 1/R₁ + 1/R₂ + … + 1/R_n

The result is always less than the smallest resistor in the network. Enter your values in ohms and the total updates instantly — all in your browser.