Voltage Divider Calculator
Enter any 3 of the 4 values (Vin, R1, R2, Vout) and calculate the missing one, plus the current through the divider.
VinInput voltage
VoutOutput voltage
R1Top resistor
R2Bottom resistor
Enter 3 values to calculate the 4th
Result
Reference formulas
A voltage divider produces a fraction of the input voltage using two series resistors. Vout is proportional to R2 relative to the total resistance R1 + R2.
Vout=Vin×R2R1 + R2
Vin=Vout×R1 + R2R2
R1=R2×Vin − VoutVout
R2=R1×VoutVin − Vout
I=VinR1 + R2