Geometric Characteristic Symbols

What is GD&T?

GD&T stands for Geometric Dimensioning and Tolerancing, as defined by ASME Y14.5M-1994.

GD&T: An International Language
Geometric dimensioning and tolerancing is an international language used on drawings to accurately describe a part. The language consists of a well-defined set of symbols, rules, definitions, and conventions that can be used to describe the size, form, orientation, and location tolerances of part features.

GD&T: An Exact Language
Geometric tolerancing is an exact language that enables designers to “say what they mean” on a drawing, thus improving product designs. Production uses the language to interpret the design intent, and inspection looks to the language to determine set up.

GD&T Provides Uniformity
By providing uniformity in drawing specifications and interpretation, GD&T reduces controversy, guesswork, and assumptions throughout the manufacturing and inspection process.