Wheatstone Bridge Output Calculator
Calculate unloaded bridge differential voltage, Thevenin output resistance and balancing resistance.
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Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Treat both bridge arms as voltage dividers across the same supply, with an open output between midpoints.
Vout=Vs[R2/(R1+R2)−R4/(R3+R4)]; Rth=(R1||R2)+(R3||R4)
Worked example
With 5V supply, R1=R2=R3=100Ω and R4=120Ω, left midpoint is2.5V, right≈2.72727273V, giving output≈−227.272727mV. R4=100Ω balances it.
Assumptions and input details
All resistances must be positive. Supply can be signed and is applied top-to-bottom on both arms. Output is left midpoint minus right midpoint. Ideal source and infinite-impedance measurement are assumed; bridge loading, lead resistance, temperature drift, sensor calibration and real amplifier input behavior are excluded. The balancing R4 is a calculated target, not a selected commercial part.
References: OpenStax: bridge null measurements
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
SI prefixes are explicit: for example, milli means one thousandth, micro one millionth and kilo one thousand. Changing a unit changes the interpretation of the entered number.
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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