Parallel Resistance Calculator
1/R = 1/R₁ + 1/R₂ + … — find equivalent resistance of resistors in parallel.
Result
Equivalent resistance
59.9768 Ω
Always less than the smallest individual: 100.00 Ω.
- Inputs100, 220, 470 Ω
- Sum of 1/R0.016673 /Ω
- R_eq59.9768 Ω
- Min input100.00 Ω
Step-by-step
- Sum reciprocals: 1/R = 1/100 + 1/220 + 1/470 = 0.016673.
- R_eq = 1 / 0.016673 = 59.9768 Ω.
How to use this calculator
- Enter resistance values separated by commas.
- Read equivalent resistance.
About this calculator
Resistors in parallel: the reciprocal of total equals the sum of reciprocals. The equivalent resistance is always less than the smallest individual resistor. Special case: two resistors → R₁R₂/(R₁+R₂). Three or more identical R → R/n.
Frequently asked
Because adding paths always lowers resistance — current flows through every available path. Mathematically, the reciprocal sum makes the result smaller.
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