Stackup

Stack what you measure and what it must meet

Result

Contributors sens. +1 adds to the gap, −1 closes it, 0.5 for a diameter acting as a radius

# Dimension Part / source Nominal Tol + Tol − Sens. Distribution k (σ at tol) Var. share Row actions

Tolerances are magnitudes: 10 +0.05 / −0.02 shifts the mean to 10.015. Uniform suits flatness, float and clearance fits; triangular suits hand assembly; normal suits capable molded or machined features.

Distribution Monte Carlo of the assembled gap

Spec limits Worst case Mean Simulated assemblies

Where the variation comes from

Loop diagram green opens the gap, red closes it, blue is the result

Want this in Excel or Google Sheets?

The free Stackup Lite workbook does worst case, RSS, Cpk and ppm with live formulas, and works in Excel and Google Sheets.

⇩ Stackup Lite (.xlsx) Pro workbook →

Runs entirely in your browser — stacks are saved on this device only. Stackup is an engineering aid, not a substitute for a reviewed tolerance analysis. Made by Juwen Lie.