Tolerance Stack Up Calculator
Compare worst-case and independent RSS spread for a signed three-dimension assembly chain.
YOUR CALCULATION
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
Form the signed assembly chain, add absolute limits for worst case and separately calculate the independent root-sum-square quantity.
Nominal=A−B−C; worst-case half-range=tA+tB+tC; RSS=√(tA²+tB²+tC²)
Worked example
100−60−20 mm gives 20 mm nominal. Limits ±0.2, ±0.1 and ±0.1 mm give worst-case ±0.4 mm; RSS quantity is 0.244948974 mm.
Assumptions and input details
Worst case uses hard limits. RSS is a standard deviation only if entered spreads are independent standard deviations; tolerance limits do not automatically become Gaussian standard deviations. Correlations and process offsets are excluded.
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Choose from 23 length definitions, including explicitly labelled regional measures. Area conversions square the length factor; geometric volumes cube it.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
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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