A voltage divider simulator, with a meter on it
Beginner
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A voltage divider is resistors in series across a supply, with a wire taken off a joint between them. The same current flows through every resistor, so the supply splits between them in proportion to their resistance. It is the circuit behind every potentiometer, every sensor read on an analog pin and every level shifter made of two resistors.
The circuit above is three 10 k resistors in a chain from 5 V to ground on a breadboard, and a multimeter with its red lead on the lower joint and its black lead on ground. Three equal resistors split 5 V into three equal parts, so the lower joint sits at one third of 5 V, about 1.67 V, and the upper joint at two thirds, about 3.33 V. Press Run and the meter reads it. Move the red lead to the upper joint and it reads the other.
This is a simulation of the circuit, not a drawing of it. The resistors are solved as resistors: change one of them in the properties panel and every voltage moves to where the formula says it should, Vout = Vin x R2 / (R1 + R2). Try 10 k over 4.7 k and the joint drops to about 1.6 V. The multimeter is a part with its own input resistance, 10 megohms on the volts range, the way a real meter loads a high-resistance divider by a hair.
The meter does more than volts. Switch it to amps and put it in series with the chain, and it reads the 167 microamps that 5 V pushes through 30 k. Switch it to ohms and put it across one resistor with the supply removed, and it reads the 10 k. Continuity beeps when the leads touch the same strip of the breadboard. These are the four things anybody does with a meter on a first circuit, and they work here the way they work on a bench.
Press Shift+O for the DC operating point and every net is labeled with its voltage at once. Open Analysis in the more menu and sweep one resistor’s value to see the tap voltage trace out the divider formula as a curve.
When you are ready for the next step, read why a divider makes a poor power supply: put a load on the joint and watch the voltage fall.
Questions
Is the voltage divider simulation accurate?
Resistors are solved exactly, and the meter has its real 10 megohm input on the volts range, so the reading is the divider’s voltage less the tiny amount the meter itself draws, just as on a bench.
Do I need an account to use it?
No. The editor opens and runs without one. You need an account to save a project to the cloud or join a class.
Build this for real
Open the editor, change a value and watch the number move with it. Nothing to install, and no account needed.