Voltage DividerX
Enter 3 of the 4 values. When entering the 3rd value, the remaining 4th value will be calculated.
R1 Ω
R2 Ω

Note: There are different voltage dividers. This app only handles resisitive dividers, when both impedances, R1 and R2, are purely resistive.
See Wikipedia's Voltage Divider article for other voltage dividers.