Voltage Divider Calculator

Step down a sensor or logic signal safely — compute Vout from two resistors, or find the R2 you need to hit a target voltage.

Input voltage (Vin)

R1 (top resistor)

R2 (bottom resistor)

Rule of thumb: keep divider current between ~0.1mA–10mA. Too low and noise/leakage skews your reading; too high and you waste battery power.

Output voltage

— V

Divider current: —
Power dissipated: —

⚠ This divider draws under 1mA — fine for high-impedance ADC inputs, but avoid it if the downstream circuit pulls real current, since loading will drop Vout below this value.

Tap junction maps to down-converted output signal

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