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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