Tolerance Stack Up Calculator May 2026

Worst-case or RSS? Learn how to build a tolerance stack-up calculator in Excel or use our free web tool to predict assembly fit before you cut metal.

Stop Guessing: How to Use a Tolerance Stack-Up Calculator (Free Template Inside)

5 minutes We’ve all been there. You design ten perfect parts, but when they come together on the assembly line, the shaft won’t fit in the hole. Or the gap between two covers is 0.5mm too wide. tolerance stack up calculator

Assign a “+” if the dimension increases the gap/stack, “-” if it decreases.

– no email required. 👉 [Link to downloadable Excel calculator or Google Sheets copy] About the author: [Your name] is a mechanical engineer with [X] years in [industry]. You can find more GD&T and tolerance analysis guides at [your website]. Worst-case or RSS

Pick one critical gap in your current assembly. Build the Excel sheet above. Compare worst-case vs RSS. You’ll be surprised how often your initial tolerances are either too tight (expensive) or too loose (non-functional).

The culprit? .

Example spreadsheet structure: