How to use the resistors in parallel calculator
Equivalent resistance of resistors in parallel. Enter resistor 1, resistor 2, resistor 3 in the fields above; the equivalent resistance is computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- R1 — Resistor 1 (Ω)
- R2 — Resistor 2 (Ω)
- R3 — Resistor 3 (Ω)
Worked example
With resistor 1 = 100 Ω, resistor 2 = 220 Ω, resistor 3 = 330 Ω, the calculator gives equivalent resistance ≈ 56.89655 Ω.
Frequently asked questions
What is the formula for the resistors in parallel calculation?
Equivalent resistance (Ω) = 1 / (1 / R1+1 / R2+1 / R3). Here R1 is resistor 1 (Ω), R2 is resistor 2 (Ω), R3 is resistor 3 (Ω).
What inputs do I need for the resistors in parallel calculator?
You need resistor 1 in Ω, resistor 2 in Ω, resistor 3 in Ω. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.