AutoCAD BLOCK Command: How to Create a Block Definition

Creates a reusable block definition from selected objects in the current drawing.

Command: BLOCK
Aliases: B
English name: Block

The AutoCAD BLOCK command turns the objects you select into a named block definition. Once defined, the block can be placed anywhere in the drawing as many times as you like with INSERT. It is used for repeated parts such as doors, windows, fixtures, outlets and title blocks.

The command opens the Block Definition dialog. You give the block a name, set its base point (the point the cursor holds when inserting) and select the objects. Retain, Convert to block or Delete decide what happens to the original objects.

A block definition is stored only in the current drawing. To save a block as a separate DWG file for use in other drawings, use WBLOCK. The command-line version is -BLOCK.

How to use it

Type BLOCK or B and press Enter.
Enter a name in the Name box.
Under Base point, click Pick point and pick the base point.
Under Objects, click Select objects, select the objects, and choose Convert to block, Retain or Delete.
Click OK to create the block.

Options

Base point: The reference point used when the block is inserted; pick it on screen with Pick point.
Retain: Keeps the selected objects in the drawing as separate objects.
Convert to block: Replaces the selected objects with an instance of the new block.
Delete: Removes the selected objects from the drawing after the block is defined.
Annotative / Scale uniformly / Allow exploding: Controls annotation scaling, uniform scaling and whether the block can be exploded.
Open in block editor: Opens the new block in the Block Editor after you click OK.

Notes and tips

Draw block contents on layer 0 with ByLayer color so the block takes on the color and linetype of the layer it is inserted on.
Put the base point at a logical spot such as a corner, center or connection point to make insertion easier.
To change an existing block, edit it with BEDIT instead of redefining it from scratch.