Voltage divider
Calculate, convert and check circuit values in your browser.
Inputs
Results
- Input voltage
- 12 V
- Output voltage
- 6 V
- Resistance R₁
- 1,000 Ω
- Resistance R₂
- 1,000 Ω
- Current
- 0.006 A
Formula and assumptions
Vout = Vin × R₂ / (R₁ + R₂)
Questions, examples and engineering limits
Calculate divider output or solve Vin, R1 or R2. Learn loading error, resistor ratio and why a resistor divider is not a regulated power supply.
Content updated:
How is Voltage Divider Calculator with Reverse Resistor Solving calculated?
Use Vout = Vin × R₂/(R₁+R₂). Calculate divider output or solve Vin, R1 or R2. Learn loading error, resistor ratio and why a resistor divider is not a regulated power supply.
Sources: openstax.org [1]
How do I calculate this example: Vin = 12 V, R₁ = R₂ = 1 kΩ?
Vout = 6 V; I = 6 mA. This is a calculated example under the model stated above; it is not a measured component specification.
Which units does Voltage Divider Calculator with Reverse Resistor Solving use?
V, Ω; R₁ above output, R₂ to ground. Convert prefixes before substituting values; keep the input and output units attached to every number.
Sources: openstax.org [1]
Why does the output fall when I connect a load?
The load is in parallel with the lower resistor. Replace R₂ by R₂ ∥ Rload before calculating; the unloaded divider formula overestimates loaded output.
Sources: openstax.org [1]
Can a divider power a microcontroller?
Usually no. Variable load current changes output voltage and wastes power. Use a suitable regulator; dividers are commonly used for sensing.
Sources: openstax.org [1]
Do equal resistor ratios behave identically?
Only the ideal unloaded ratio is identical. Absolute resistance changes current, source impedance, loading sensitivity and noise.
Sources: openstax.org [1]
Answers use the stated model and units. Examples are calculated values, not measurements or component ratings.