🔌 Voltage Divider Calculator
Calculate the output voltage of a simple two-resistor voltage divider circuit.
What This Calculator Does
This tool calculates the output voltage produced by a simple voltage divider — two resistors placed in series across a voltage source, a very common building block in electronics used to scale a voltage down to a lower level.
The Formula
The output voltage is calculated using Vout = Vin × (R2 / (R1 + R2)), where Vin is the input (source) voltage, and R1 and R2 are the two series resistors in ohms, with Vout measured across R2. The calculator also reports the voltage dropped across R1 and the current flowing through the circuit.
Practical Notes
Voltage dividers are used to create reference voltages, condition sensor signals, and step down voltages for microcontroller inputs. This ideal formula assumes no current is drawn from the Vout node (a high-impedance load); connecting a load resistor in parallel with R2 will change the actual output voltage.
- Provided for general educational and hobbyist planning purposes, not for certified electrical design.