Voltage Divider

Calculate Vout from Vin, R1, and R2. Shows divider current and resistor power.

Inputs

Notes: R1 is between Vin and Vout, R2 is between Vout and GND. Load is treated as parallel with R2.

Results

Vout
Divider current
Power (R1)
Power (R2)
Power (Load)
Effective bottom resistance
Ratio (Vout/Vin)
If you provide a Load value, the output voltage drops depending on the parallel resistance.

FAQ

Why does load resistor change Vout?

A load forms a parallel network with R2, changing equivalent resistance and lowering output voltage.

How should I choose divider resistor values?

Balance low current consumption and noise sensitivity. Very high resistances can be more noise-prone.

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