What Is Trim Mode AutoCAD?

In AutoCAD, Trim mode is a powerful editing tool that allows you to selectively remove unwanted lines, arcs, or other objects from your drawing. It helps you clean up and refine your design by eliminating unnecessary elements. When you activate Trim mode, it prompts you to select cutting edges and then trims or extends objects to those selected edges.

Activating Trim Mode

To activate Trim mode in AutoCAD, you can use the TRIM command or simply press the TR shortcut key on your keyboard. Once activated, the command line will prompt you to select cutting edges.

Selecting Cutting Edges

To select a cutting edge, click on a line, arc, or polyline segment that you want to use as a boundary for trimming other objects. The selected cutting edge will be highlighted in a distinctive color (usually green) to indicate that it has been chosen.

Note: You can select multiple cutting edges by holding down the Shift key while selecting additional objects. This allows you to trim multiple objects with a single operation.

Trimming Objects

Once you have selected your cutting edges, AutoCAD will automatically trim or extend the objects based on their relationship with the chosen boundaries. Objects that intersect with the cutting edges will be trimmed back to those boundaries. Objects that do not intersect but are close enough will be extended until they intersect with the cutting edges.

Note: You can easily switch between trimming and extending modes while in Trim mode by pressing the Enter key on your keyboard.

Trimming Multiple Objects

In addition to trimming individual objects, AutoCAD also allows you to trim multiple objects at once. To do this:

  • Select all the objects that you want to trim.
  • Press Enter to confirm your selection.
  • Select the cutting edges as usual.

All the selected objects will be trimmed or extended based on their relationship with the cutting edges you have chosen.

Trimming With a Fence

In AutoCAD, you can also use a fence to define the boundary for trimming objects. A fence is a polyline that acts as a temporary boundary. To use a fence:

  • Type FENCE in the command line or press F and then Enter.
  • Create a polyline by specifying its vertices.
  • Press Enter to confirm your fence selection.

Now, when you activate Trim mode and select objects, they will be trimmed or extended based on their relationship with the defined fence.


Trim mode in AutoCAD is an essential tool for precise editing and cleanup of your drawings. It allows you to selectively remove unwanted lines and arcs, improving the clarity and accuracy of your designs. By mastering Trim mode, you can efficiently refine your drawings and create professional-looking designs in AutoCAD.