ISO 2768 general tolerance calculator

The ± tolerance a drawing's "ISO 2768-m" note allows for any dimension.

ISO 2768-1 sets tolerances for dimensions that have none written next to them, by size range and class (f fine, m medium, c coarse, v very coarse). A title block note such as "ISO 2768-mK" means class m for linear dimensions. Inch sizes are converted to millimetres for the lookup.