MAXScanner electronics calculator
Updated 2026-09-16
Wheatstone Bridge Calculator — Balance, Output Voltage & Unknown Resistance
Calculate Wheatstone bridge differential midpoint voltage from four entered arms and report the balanced R4 implied by R1, R2 and R3.
Inputs
Results
Bridge output 0 V
Left midpoint 2.5 V
Right midpoint 2.5 V
Balanced R4 from R1, R2 and R3 1,000 Ω
Bridge state Balanced
More actions
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Your calculation, step by step
- 1.Left midpoint: Vs × R2/(R1+R2) = 2.5 V; Right midpoint: Vs × R4/(R3+R4) = 2.5 V.
- 2.Bridge output: left − right = 0 V; Balanced R4 from R1, R2 and R3: R2×R3/R1 = 1,000 Ω.
Formula, example and limits
Vout=Vs×R2/(R1+R2)−Vs×R4/(R3+R4); balance when R1/R2=R3/R4; balanced R4=R2×R3/R1.
Four equal resistors produce zero differential bridge output.
- Bridge output is unloaded/high impedance.
- Resistors are treated as ideal DC values.
Frequently asked questions
When is the bridge balanced?
When the resistor ratios match, the two midpoint voltages are equal.
Can it solve an unknown arm?
The runtime reports the R4 value that would balance the bridge from the entered R1, R2 and R3.