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Calculate unloaded divider output, current and resistor power from explicit values.
Calculate unloaded divider output, current and resistor power from explicit values.
vin=12
r1=1000
r2=2000Output voltage: 8 V
Formula: Vout = Vin × R2 / (R1 + R2)
Substitution: 12 × 2000 / (1000 + 2000) = 8 V
Total resistance: 3000 Ω
Divider current: 0.004 A
R1 power: 0.016 W
R2 power: 0.032 WPaste content, enter parameters or choose the files you need in “Input voltage, R1 and R2”.
Choose “Calculate divider” for the job. Processing runs in this browser.
Review the result under “Divider result”, then copy or download it after checking the output.
Result guide
For an ideal two-resistor divider, Vout is measured across R2: Vout = Vin × R2/(R1 + R2). The calculator also reports total resistance, divider current, and each resistor's power.
For R1 above the output node and R2 to ground, the ideal unloaded output is Vout = Vin × R2/(R1 + R2).
A load in parallel with R2 reduces the effective lower resistance, so the real output is usually lower than this unloaded result. Model the parallel load separately for design work.
Enter both resistors in the same unit. The sample uses ohms, so current is returned in amperes and power in watts.
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