Set unit options

Unit options allow you to specify which units of measurement are available in various contexts in your project.

To set Unit options, do the following:

1. Open the ArcGIS AllSource settings page in one of the following ways:
   • From an open project, click the Project tab on the ribbon.
   • From the start page, click the Settings tab .
2. In the list of side tabs, click Options.
3. On the Options dialog box menu, under Project, click Units.

   Note:

   Project options apply only to the currently open project. If there is no open project, they are not enabled.

Add a new unit

You can add different units of measurement to the list of available distance, angular, area, location, and direction units.
1. From the Units page, expand one of the unit types and click <Select Unit Code> at the bottom of the table. Choose from the list of available units.

   

You can edit some aspects of the unit display directly on the Options dialog box by clicking a cell in the Name, Plural, or Abbrev columns. The default unit can also be set by clicking the buttons under the Default column.

Format a unit

In addition to editing the display names and abbreviations for distance, angular, area, location, and direction units on the Options dialog box, you can also customize the numeric display by opening the Numeric Format or Direction Formatting dialog box.
1. From the Units page, expand one of the unit types.
2. For additional formatting options, right-click an existing unit and click Edit unit format.

   

   Depending on the units, the Numeric Format or Direction Formatting dialog box appears. On the dialog box, you can modify a variety of formatting settings, such as the number of decimal places and significant digits that are displayed for the unit you've selected.

Types of units

On the Options dialog box, you can configure eight types of units. The first five are geographic measures that are used to describe locations on the earth, while the last three are page and symbol measures that refer to the placement of objects on a page. Map and display units are configured elsewhere in the application.

Distance units

Distance units are the units in which you can specify or report distances between locations. These units include feet, meters, kilometers, and miles. They commonly appear in editing tools, where you can specify values for length on constraint dialog boxes that use the default unit of measurement. The list of distance units on the Options dialog box is also available in the Measure Distance tool and network analysis tools. For more information, see Distance units for editing.

Note:

The Metric and Imperial unit options in the Measure Distance tool automatically change between smaller units of measurement (feet and meters) and larger units of measurement (miles and kilometers), depending on the length of the measurement.

Angular units

Angular units are the unit of measurement on a sphere or spheroid. Some map projection parameters, such as the central meridian and standard parallel, are defined in angular units. The default direction is specific to your locale. The default setting is degrees. For more information, see Direction units for editing.

Area units

Area units are used to describe the size of two-dimensional planes. These units are available in the Measure Area tool .

Location units

Location units are used to describe an absolute geographic location in x,y format and are related to the coordinate system of the project. The list of location units appears on the pop-up dialog boxes of many feature editing tools, such as Absolute X,Y,Z and the Move tools. These units adjust automatically to use units that correspond to whichever coordinate system is set. For example, if you use an editing tool while in an unprojected coordinate system, the list of units will not include projected units. The full list of location units appears when you select display units for your map. For more information, see Distance units for editing.

Direction units

Direction units reference a meridian to describe the spatial relationship between a direction and a reference axis. These units allow you to type direction values in azimuth, polar, or quadrant bearing units. For more information about these types of units, see Direction units for editing.

Page units

These units of measure, usually millimeters or inches, are used to arrange map elements on a page for printing. New units cannot be added to the list of page units. Layout templates always appear in their designated units, but the default unit of measurement is used for creating custom page sizes. These units are used primarily within layouts.

2D symbol display units

These units are used to render dimensions of shapes, distance tolerances, and offsets both on a computer screen and on a printed map. These units are used for elements within two-dimensional symbology, such as outline width and point symbol size. The default unit is point (pt). New units cannot be added to the list of 2D symbol display units. For more information, see Symbol units and size.

3D symbol display units

These units are used to render dimensions of shapes, distance tolerances, and offsets for three-dimensional symbols. The unit chosen here applies to a symbol's length, width, and height. The default unit is meters. Units added to the list of distance units automatically appear in the list of 3D symbol display units. For more information, see Symbol units and size.