Does ±0.05 mm mean entering 0.05?

Enter 0.10 mm because this model uses the entire tolerance width. Entering the half width understates the assembly variation.

Do subtracting dimensions cancel their tolerances?

No, independent extreme limits can combine adversely even when nominal dimensions subtract. Their full worst-case widths still add for unit-magnitude sensitivities.

Can I use a root sum of squares instead?

Only with an appropriate statistical model and supported distributions. Drawing limits alone do not establish standard deviations or an assembly acceptance probability.

What if my chain has fewer than four features?

Set the unused feature widths to zero. Include every independent dimension that contributes to the selected assembly measurement.

Quality & Metrology calculator

Tolerance Stackup Calculator

Check whether four drawing tolerances fit a linear assembly budget. Enter full widths, including twice the plus/minus value for symmetric tolerances.

What this calculator does

Check a four-feature worst-case tolerance width against the drawing’s assembly budget.

Formula used

Full stack width = width 1 + width 2 + width 3 + width 4
Symmetric half width = full stack width ÷ 2
Budget margin = allowed assembly width − full stack width

Inputs explained

Feature 1 Full Width: Upper minus lower limit for the first chain feature.
Feature 2 Full Width: Full drawing tolerance width of the second feature.
Feature 3 Full Width: Full drawing tolerance width; zero for an absent feature.
Feature 4 Full Width: Full drawing tolerance width of the fourth feature.
Allowed Assembly Width: Maximum full assembly tolerance width on the approved drawing.

How to use the result

Best suited to drawing allocation Review, linear assembly clearance.
Angular, nonlinear and compliant assemblies need geometry-specific analysis. Worst-case width gives no statistical yield prediction.

Current U.S. benchmarks

U.S. manufacturing runs at 75.7% of capacity (Federal Reserve, Aug 2026). New factory orders are up 8.5% year over year (Census).

Common questions

Does ±0.05 mm mean entering 0.05? Enter 0.10 mm because this model uses the entire tolerance width. Entering the half width understates the assembly variation.
Do subtracting dimensions cancel their tolerances? No, independent extreme limits can combine adversely even when nominal dimensions subtract. Their full worst-case widths still add for unit-magnitude sensitivities.
Can I use a root sum of squares instead? Only with an appropriate statistical model and supported distributions. Drawing limits alone do not establish standard deviations or an assembly acceptance probability.
What if my chain has fewer than four features? Set the unused feature widths to zero. Include every independent dimension that contributes to the selected assembly measurement.

Last reviewed 2026-10-06.