Parallel resistor calculator
Series and parallel totals for up to six resistors, and the current through each branch when a known current splits between them.
Parallel total
599.8Ω
- Series total
- 7.9 kΩ
- Resistors counted
- R1, R2, R3
Method
How this is calculated
R_series = R1 + R2 + ... + Rn R_parallel = 1 / (1/R1 + 1/R2 + ... + 1/Rn) I_k = I_total · R_parallel / R_k (current divider)
- Empty slots
- A resistor left at 0 is ignored, so two values give the familiar R1 · R2 / (R1 + R2).
- Current divider
- Every parallel branch sees the same voltage, I_total · R_parallel, so the lowest resistance carries the most current.
FAQ
Questions
Half of one. Two 10 kΩ resistors in parallel are 5 kΩ; n equal resistors in parallel are R / n.
Each resistor adds a path for current. 1 Ω, 2 Ω and 2 Ω in parallel come to 0.5 Ω, below the 1 Ω branch.
In inverse proportion to resistance. 6 A into 1 Ω, 2 Ω and 2 Ω in parallel splits as 3 A, 1.5 A and 1.5 A, because all three see 3 V.
To reach a value between E-series steps, or to share the power. Two 1/4 W resistors of equal value in parallel can handle 1/2 W between them.
Related
Related tools and reading
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