A worked example
5 V across two 10 kΩ resistors gives 2.5 V unloaded; a 10 kΩ load changes it to about 1.667 V.
Voltage divider
Calculate unloaded or resistively loaded output voltage with current and resistor power estimates.
YOUR LITTLE WORKBENCH
Voltage divider
Start with an example and change it to your setup. Results update as you type.
Calculation method+
Vout = Vin × Reffective ÷ (Rtop + Reffective). With a load, Reffective = Rbottom || Rload.
YOUR LIVE RESULT ✦
Output voltage
2.5 V- Source current
- 0.25 mA
- Top resistor power
- 0.625 mW
- Bottom resistor power
- 0.625 mW
- Effective bottom resistance
- 10,000 Ω
This is an ideal DC resistive model. It excludes source impedance, tolerance and dynamic loading. Inputs use volts and kΩ, with a 0–60 V model range.
THE METHOD / 01
Know what goesinto your result.
Vout = Vin × Reffective ÷ (Rtop + Reffective). With a load, Reffective = Rbottom || Rload.
Keep the assumptions clear
This is an ideal DC resistive model. It excludes source impedance, tolerance and dynamic loading. Inputs use volts and kΩ, with a 0–60 V model range.
A FEW USEFUL ANSWERS
Good to know.
Are my inputs uploaded?
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Do I need an account?
No sign-up, paid API or subscription is required. Both language versions use the same calculation logic.
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