Voltage Divider Calculator
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Formula: Vout = Vin × R2 / (R1 + R2)
Voltage Divider Calculator
A voltage divider uses two resistors in series to create a lower voltage from a higher one. It is one of the most common circuit building blocks.
Conversion Formula
Vout = Vin × R2 / (R1 + R2)
Vout = Vin × R2/(R1+R2). The output is taken across R2 (the bottom resistor).
Step-by-Step Examples
Vin=12V, R1=10kΩ, R2=10kΩ = Vout=6V
12 × 10000/(10000+10000) = 6V
Vin=5V, R1=3kΩ, R2=1kΩ = Vout=1.25V
5 × 1000/(3000+1000) = 1.25V
Frequently Asked Questions
What is a voltage divider?
A voltage divider is a simple circuit with two resistors in series that produces an output voltage that is a fraction of the input voltage.
When would I use a voltage divider?
To step down a voltage for a sensor input, create a reference voltage, or bias a transistor.
Can I use a voltage divider as a power supply?
No, voltage dividers are not suitable for powering loads because the output voltage drops significantly under load.