Voltage divider
No load on the output.
Method
Vout = Vin × R2 / (R1+R2). Worked case: 12 V, 1 kΩ over 2 kΩ is 8 V.
What to write beside the result
A review can only check this figure if the inputs sit next to it. Write the value, the unit and the assumption the form used. A diameter in millimetres and a diameter in metres are not the same reading. A force in kilonewtons divided as if it were newtons is a thousand-fold error.
The result is the arithmetic on this page. It is not a utilisation, not a selected product, and not a clause from a standard. If the number is going into a shared container, name the page, the date and the inputs. The file-name checker does not read the calculation.
Logic: how this figure is built.
How to read a divider
This page answers the unloaded output of a two-resistor divider: Vout = Vin × R2 / (R1 + R2). A 12 V supply with 1 kΩ over 2 kΩ gives 8 V at the junction if R2 is the lower resistor. It is a resistor ratio. It is not a power-supply design.
The formula assumes no current leaves the junction. A load across R2 changes the lower resistance and the output falls. If the next device draws current, this page is the open-circuit estimate only. Say that when you quote it.
Resistors must be in the same unit. 1 kΩ and 2,000 Ω are the same pair as 1 kΩ and 2 kΩ. Mixing a kilohm with an ohm moves the ratio by a thousand. The page does not know which resistor you meant as R2, so the labels on the form are the ones that count.
Use it to check a sensor bias or a reference tap before it is built. It does not give the power in either resistor, the tolerance stack, or a safe dissipation. Those need the current and the resistor rating.
Last checked 3 October 2026. See the disclaimer.