About rulers

Rulers in Illustrator are guides along the top and left edges of the document that show measurement units. They help you align, place, and measure objects precisely.

Types of rulers

Illustrator provides two distinct ruler systems that serve different purposes in your workflow:

• Global rulers are displayed at the top and left edges of the window, with the origin point (0,0) at the upper-left corner of the document. Use these when positioning elements relative to the entire document.
• Artboard rulers are displayed at the top and left edges, but are specific to the active artboard. The origin point is set at the top-left corner of that artboard. These are especially useful when working with multiple artboards, as they provide measurements relative to each individual artboard.

About the ruler origin

The ruler origin is the point where 0 appears on both the horizontal and vertical rulers, serving as the reference for all measurements in your document. Illustrator allows you to customize the origin to match your design needs:

• For global rulers, the default origin is at the upper-left corner of the first artboard.
• For artboard rulers, the default origin is at the upper-left corner of the active artboard.
• You can assign different origin points for individual artboards when using artboard rulers.
• Changing an artboard ruler origin does not affect pattern fills applied to objects.

Coordinate system

Illustrator uses a coordinate system to precisely position elements within a document:

• The horizontal (x) axis increases in value as you move to the right.
• The vertical (y) axis increases in value as you move downward.

The coordinate system for scripting follows backward compatibility. As a result, Y-coordinate values in scripting may differ from those shown in the user interface.