Potential Divider Calculator

These calculators perform calculations for potential divider circuits. The first one calculates the voltage from known resistor values, the second finds suitable resistor values if the desired output voltage is known. The third calculates R2 given V1, V2 and R1. Preferred resistor values are also calculated for the second and third calculators. Use the radio buttons on each calculator to select the preferred value series to use.

Potential Divider Circuit Showing Notation Used in Calculators

Calculate Voltage Out (V2) from Resistors (R1 & R2):

Enter R1: Arrow V2 = ?
Enter R2:
Enter V1:

Calculate Resistors (R1 & R2) from Voltage Out (V2):

Enter V1: Arrow R1 = ?

R2 = ?

Preferred R1 = ?

Preferred R2 = ?
Enter V2:
Enter Total Resistance (R1 + R2):
               
Select preferred series (optional):
E12    E24    E48    E96    E192

Calculate Resistor  R1  from Voltage Out (V2) and R2:

Enter V1: Arrow R1 = ?

Preferred R1 = ?
Enter V2:
Enter R2:
Select preferred series (optional):
E12    E24    E48    E96    E192

Formula:

The voltage out of the divider is determined by the resistor values using the equation:

V2 = (R2 / (R1 + R2)) * V1

For further details about the operation of a potential divider see the technical data section here.

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