Current Divider Calculator
Calculate how current splits between parallel branches.
About Current Divider Calculator
Parallel branches share the same voltage, so current divides in proportion to conductance — the lowest resistance takes the most current. Adding conductances is the simplest route to the combined resistance. Current sharing in parallel devices is never perfectly equal because resistances differ, which is why paralleled semiconductors need ballast resistors.
Formula
Current Divider
I_n = I_total × (1/R_n) ÷ Σ(1/R); equivalently I_n = V ÷ R_n
- conductance
- Reciprocal of resistance; parallel branches add conductance
Worked example
With the default values below, Current Divider Calculator returns Current in Branch 1 of 1.79930. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Total currentminimum 0 A
- 3 A
- Branch 1 resistanceminimum 0.01 ohm
- 100 ohm
- Branch 2 resistanceminimum 0.01 ohm
- 220 ohm
- Branch 3 resistanceminimum 0.01 ohm
- 470 ohm
Results
- Current in Branch 1
- 1.79930 A
- Current in Branch 2
- 0.81787 A
- Current in Branch 3
- 0.38283 A
- Combined Parallel Resistance
- 59.9768 ohm
- Voltage Across the Parallel Group
- 179.93039 V
Step by step
- 1Values used
- 2Current Divider
- 3Current in Branch 1= 1.79930 A
- 4Current in Branch 2= 0.81787 A
- 5Current in Branch 3= 0.38283 A
- 6Combined Parallel Resistance= 59.9768 ohm
- 7Voltage Across the Parallel Group= 179.93039 V
Assumptions and limits
- The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 5 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Current Divider calculated?
I_n = I_total × (1/R_n) ÷ Σ(1/R); equivalently I_n = V ÷ R_n Parallel branches share the same voltage, so current divides in proportion to conductance — the lowest resistance takes the most current. Adding conductances is the simplest route to the combined resistance.
Why does Current Divider matter?
Current sharing in parallel devices is never perfectly equal because resistances differ, which is why paralleled semiconductors need ballast resistors.
What values do I need to enter?
This calculator takes 4 inputs: Total current, Branch 1 resistance, Branch 2 resistance, Branch 3 resistance. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.