Voltage Divider Calculator
Enter any three values to solve for the fourth in a classic two-resistor voltage divider.
Enter any three values; the fourth is calculated automatically.
Voltage divider basics
A voltage divider uses two series resistors to produce a lower output voltage: Vout = Vin × R2 / (R1 + R2). The same current flows through both resistors. This calculator assumes no load on the output — real circuits may need a buffer if the load draws significant current.
