Pipe Label Sizes and Fonts

The size of your label and font is based on pipe diameter

pipe label sizes and fonts

The letters on pipe labels should be a minimum of 1/2" high, and should increase in size as the pipe diameter increases. The following table indicates ANSI-recommended pipe label lettering height for various pipe sizes.

Outside Pipe Diameter (OD) Letter Height

.75" to 1.25"


1.5" to 2"


2.5" to 6"


8" to 10"


over 10"


Pipe Labeling Fonts

Pipe labels are required to have bold, readable fonts which are easily viewed and understood at a distance and at a variety of angles. The height of the letters is important, but it's also important that the lettering be legible. Make sure to use proportional fonts, such as Arial, Arial Bold, Arial Black, and Arial Narrow, or other highly readable sans-serif fonts.