Circuit Analysis calculator

Current Divider Calculator

Use this current divider calculator for resistive parallel networks where a known total current enters 2 to 6 resistor branches. The calculator finds equivalent parallel resistance, current through each branch, branch power, common network voltage, and a Kirchhoff current law check.

Updated June 2, 2026

With 10A entering 100Ω and 200Ω parallel branches, the 100Ω branch carries about 6.67A and the 200Ω branch carries about 3.33A.

Branch current = Total current × Req ÷ Rbranch

Enter total current and 2 to 6 branch resistances below to calculate branch current, watts, and the KCL check

Calculator Inputs

Calculation Results

Enter values above to see calculation results

Calculation history

Example Calculations

Two Parallel Resistors

Current divider with R1=100 ohms and R2=200 ohms

Inputs

Total Current: 10
Current Unit: A
Resistor 1: 100
Resistor 2: 200
Resistor Unit: Ohms

How to Use

What this calculator does

This page models a resistive current divider. Enter the total current entering the node and the resistance of each branch. The calculator converts the selected units, calculates equivalent parallel resistance, then applies the current-divider rule to each branch.

Current-divider rule

For branch n in a parallel resistor network:

I_n = I_total × (R_eq / R_n)

Where R_eq is the equivalent resistance of all modeled branches and R_n is the resistance of the branch being solved. Lower-resistance branches carry more current because every branch has the same voltage across it.

Two-resistor shortcut

For exactly two parallel resistors, the branch current uses the other resistor in the numerator:

I1 = I_total × R2 / (R1 + R2)
I2 = I_total × R1 / (R1 + R2)

Worked example

Total current is 10 A, R1 is 100 ohms, and R2 is 200 ohms.

Output	Value	Check
Equivalent resistance	66.67 ohms	1 / (1/100 + 1/200)
Current through R1	6.67 A	Lower resistance branch carries more current
Current through R2	3.33 A	Branch currents sum to 10 A
Voltage across network	666.67 V	10 A × 66.67 ohms

Important limits

This is not a complete AC network solver. For inductors, capacitors, motors, transformer windings, or any branch where phase angle matters, use impedance rather than plain resistance. For building wiring and paralleled conductors, use the adopted electrical code, equipment ratings, and project engineering documents rather than relying on this electronics-style resistor screen.

Common Applications

Check branch current in parallel resistor networks

Verify current split in electronics training problems

Estimate current through each resistor in a DC sensing network

Cross-check a parallel-circuit calculation with KCL

Review branch power before choosing resistor wattage

Frequently Asked Questions

What is the current divider rule?

The current divider rule calculates how a known total current splits across parallel resistive branches. For each branch, I_n = I_total × R_eq / R_n. Because each branch has the same voltage, a lower resistance branch carries a larger share of the total current.

How do I check whether the result is correct?

Add the branch currents together. The sum should equal the total current entering the parallel network. You can also multiply each branch current by its branch resistance; every branch should show the same voltage.

Can I use this for AC circuits?

Only if each branch can honestly be represented by a resistive or steady-state equivalent value. If inductive or capacitive reactance matters, use complex impedance and phasor analysis instead of plain resistance values.

Why does the smaller resistor carry more current?

Parallel branches share the same voltage. Ohm law says I = V / R, so the branch with lower resistance draws more current at that same voltage.

Is this the same as a parallel circuit calculator?

It is narrower. This page focuses on current sharing from a known total current. A full parallel circuit calculator may also solve from voltage, equivalent resistance, conductance, and total power.