Current Divider Calculator
Splits a current between two parallel resistors. Useful for shunts, meter ranges and working out how much current a parallel path is actually stealing.
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
The formula
I₁ = I × R₂ ÷ (R₁ + R₂) I₂ = I × R₁ ÷ (R₁ + R₂)
Both resistors have the same voltage across them, so by Ohm’s law the current in each is inversely proportional to its resistance. That is why the opposite resistor ends up on the top of the fraction — and why the low-resistance branch carries most of the current.
What to watch out for
The one thing to get right is which resistor goes on top. A voltage divider puts its own resistor on the numerator; a current divider puts the other one there.
The reason is that parallel components share a voltage rather than a current. With the same voltage across both, the lower resistance passes more current — so the branch you are asking about gets a share set by its partner.
Frequently Asked Questions
What is the current divider formula?
I₁ = I × R₂ ÷ (R₁ + R₂). The resistance of the other branch appears on top, because parallel branches share a voltage and the current divides inversely with resistance.
Which resistor gets more current in parallel?
The smaller one. With the same voltage across both, the lower resistance passes proportionally more current — a 1 kΩ and a 3 kΩ in parallel split the current 75% to 25% in favour of the 1 kΩ.
How is this different from a voltage divider?
It is the mirror image. A voltage divider puts resistors in series and splits voltage in proportion to resistance; a current divider puts them in parallel and splits current in inverse proportion.