Current Divider Calculator

A current divider is a parallel circuit configuration in which the total supply current splits among multiple branches. Each branch carries a portion of the total current inversely proportional to its resistance — lower resistance draws more current, and higher resistance draws less.

The current divider rule states that the current through any branch of a parallel resistor network equals the total current multiplied by the ratio of the total equivalent resistance to that branch's resistance: I_branch = I_total × (R_total / R_branch). This works because all parallel branches share the same voltage.

In a parallel circuit, all resistors share the same voltage across their terminals. Using Ohm's Law (I = V/R), each branch current is determined by dividing that common voltage by the branch resistance. Branches with lower resistance carry proportionally more current than high-resistance branches.

The total equivalent resistance of n parallel resistors is found using the reciprocal formula: 1/R_total = 1/R1 + 1/R2 + 1/R3 + … This calculator performs that computation automatically from the resistor values you enter.

Because all parallel branches share the same voltage, a branch with lower resistance allows more current to flow through it (I = V/R). This is the inverse relationship between current and resistance in a parallel network — exactly what the current divider rule captures.

No. In a series circuit, the same current flows through every component — there is no branching. Current division only occurs in parallel circuits where multiple paths exist for current to flow. A series circuit is better described as a voltage divider.

If any parallel branch has zero resistance (a short circuit), the total equivalent resistance becomes zero and all current flows through that short-circuit branch. This calculator ignores any resistor entered as 0 to avoid division-by-zero errors — enter only positive, non-zero values for valid branches.

This calculator is designed for resistive parallel circuits using DC or simple AC analysis. For inductive or capacitive circuits, the current divider rule still applies but uses impedance (Z) instead of resistance (R). You would need to account for reactance values and phase angles in those cases.