What is the difference between dimensional tolerance and geometric tolerance on a drawing?

• A. Geometric tolerance relates to size; dimensional tolerance addresses shape
• B. Dimensional tolerance relates to size; geometric tolerance addresses shape, orientation, runout, and location
• C. Dimensional tolerance relates to material type; geometric tolerance relates to finish
• D. They are the same

Answer: (B)

Dimensional tolerance controls the size of a feature. It sets how large or small the feature can be, such as a hole or shaft diameter, with a plus/minus allowance. Geometric tolerance, by contrast, describes how the feature’s geometry can vary in shape and in its relationship to other features—things like form (flatness, straightness), orientation (perpendicularity, parallelism), runout, and true position relative to datum references.

So a dimension with tolerance that specifies a hole’s diameter is about size. A geometric tolerance that constrains where the hole must be located and how it is oriented to datum features is about the geometry and its relation to the rest of the part. This distinction is why the correct statement is that dimensional tolerance relates to size, while geometric tolerance addresses shape, orientation, runout, and location. Materials type or finish aren’t what these tolerances describe, and they are not the same concept.