What Size Font Should You Use for Dimensioning?

Dimension labels must be readable.

Dimensioning is the practice of labeling heights, widths and depths of objects on technical drawings. Readable dimension labels are essential on blueprints and architectural drawings. Type font and size contribute to drawing clarity and ease of interpretation in executing the intent of the drawings.

General Guidelines

As a drafting technician, you should limit the number of font sizes on a given drawing to three. Select and use the same font style in small, medium and large sizes. Depending upon overall lettering emphasis, the various sizes may be standard or boldface.

Font Standards

Any readable font may be used in dimensioning. Helvetica and similar types are preferred. Notes and labels should not be smaller than 1/8-inch or larger than 1/4-inch. Drawing titles should be limited to 1/2-inch.

Conversion to Point Siz

Expressed in printing terms, a single letter one inch high is 72 points high; 1/8-inch type is nine points high; 3/16-inch type is 13.5 points high; 1/4-inch type is 18 points high. To convert inches to points, divide 72 by fractions of an inch.

References

• University of Minnesota: Interior Design Student Handbook
• Victoria College: Technical Drawing Specifications
• State of Wyoming DOT: Drafting Guidelines

Resources

• Texas Tech University: CADD Manual