Tolerance Stack-Up Calculator

Inputs

Dimension count

Dim 1 direction

Dim 1 nominal (D1)

Dim 1 +/- tolerance (t1)

Dim 2 direction

Dim 2 nominal (D2)

Dim 2 +/- tolerance (t2)

Dim 3 direction

Dim 3 nominal (D3)

Dim 3 +/- tolerance (t3)

Default result

Nominal stack (S)

55 mm

Pass

3 dimensions included in the stack.

Also computed

Worst-case tolerance (T_wc) 0.23 mm

Sum of all plus/minus tolerances.

Worst-case minimum (S_min) 54.77 mm

Worst-case maximum (S_max) 55.23 mm

RSS tolerance (T_rss) 0.13748 mm

sqrt(sum(t_i^2)); use only when statistical assumptions are justified.

RSS minimum (RSS_min) 54.863 mm

RSS maximum (RSS_max) 55.137 mm

Method notes 2 notes

Worst-case stack adds the absolute tolerance of every dimension, assuming all parts hit their least favorable limit at once.
RSS stack uses sqrt(sum(t_i^2)) and assumes independent, centered variation. It is not a replacement for process capability or datum/geometric tolerance analysis.