About the Parallel Resistance Calculator
Equivalent resistance of resistors in parallel, with the current through each branch.
Also known as: resistors in parallel, equivalent resistance, parallel resistor formula.
How to use this calculator
- Enter r1, r2, r3, r4 and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
1/R_total = 1/R₁ + 1/R₂ + 1/R₃ + …
Worked example
Using the values pre-filled in the calculator above:
- R1 = 100 Ω
- R2 = 220 Ω
- R3 = 0 Ω
- R4 = 0 Ω
- Supply voltage (optional) = 12 V
the calculator returns:
- Equivalent resistance: 68.75 Ω
- Conductance: 0.014545 S
- Total current: 0.17455 A