Wheatstone Bridge Calculator
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Wheatstone Bridge Calculator
Output voltage and balance condition for a 4-resistor bridge — strain gauges, RTDs, resistive sensors
Bridge Arms & Excitation
Bridge Layout
Result
Output Voltage Vout (B to D)
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Balance Check
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VB (node B)
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VD (node D)
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Formula: with excitation across A–C, R1/R2 forming one divider (node B) and R4/R3 forming the other (node D):
VB = Vex×R2/(R1+R2), VD = Vex×R3/(R3+R4), Vout = VB − VD.
The bridge is balanced (Vout=0) when R1×R3 = R2×R4 — the classic condition used to null a bridge before a
sensor (e.g. a strain gauge replacing R4) shifts one arm's resistance and unbalances it, producing a small measurable Vout.
