Engineering Definition
Geometric Dimensioning and Tolerancing (GD&T)
A standardized symbolic language used on engineering drawings to control allowable geometric variation in form, orientation, location, profile and runout.
Why it matters
GD&T connects design intent to manufacturing setup and inspection strategy more precisely than simple plus/minus dimensions alone.
Related technical topics
Technical Literacy · Intermediate
Geometric Dimensioning and Tolerancing (GD&T)
Understand how GD&T communicates allowable geometric variation using datums, feature-control frames and standardized controls for form, orientation, location and runout.
Technical Literacy · Foundational
Engineering Drawings and Blueprints
Learn how industrial drawings communicate geometry, dimensions, tolerances, materials, finishes, assembly relationships and revision-controlled requirements.
Metrology & Quality · Intermediate
Coordinate Measuring Machines (CMMs)
Understand CMM fundamentals, probing, alignment, datum establishment and how inspection programs translate drawing requirements into measured results.