How to read the graduations on Inch Dials

As a standard convention, every number printed on the dial of an inch-reading test indicator or dial indicator represents .001" This applies to all makes and models which are inch reading. In fact, it also applies to dials on thickness gages, dial calipers, dial bore gages, and dial micrometers.

• Whether .001", .0005", or .0001" the same rule applies.
• Inch reading dials will be white, black and sometimes other colors (but not yellow which is reserved for metric dials)

Regardless of the dial's graduations, the numbers always indicate .001 inch

How to read the graduations on Metric Dials

The same principle applies to all metric dials. In this case, each number will represent 0.01 mm regardless of the gage's discrimination. For example the number 10 would represent 0.10 mm and the number 90 would represent 0.90 mm.

• By convention, metric indicators sold in the U.S.A. should have yellow dials.
• Metric dials in the rest of the world are white.

On metric gages, regardless of the dial's graduations, the numbers always indicate 0.01 mm