Corner Widgets

Shapes with corners have widgets that you can use to alter the shape of the corners, including Round, Inverted Round, and Chamfer. Corner widgets appear on all corners of a rectangle, and at the top point of a polygon. Star shapes have corner widgets that are activated by selecting the shape with the Direct Selection tool.

Editing Corners

Draw a rectangle and select the shape with the Selection tool. The corner widgets will appear as targets in each inside corner. If the targets appear small, there is a setting in Illustrator's preferences for setting the size of anchor points and corner widgets. Choose Preferences > Selection & Anchor Display… to bring up the options. Set the slider to the desired size and click OK. If the corner widgets are not showing when you select a rectangle, choose View > Show Corner Widget.

Click on a target and pull it into the center of the shape. This will result in a rounded corner, which is the default setting. Once you pull the corner into the center the maximum amount, a red line will appear alerting that you have achieved maximum “widgetness”—the point where the corner cannot be pulled in anymore.

When you've reached this maximum capacity, you will not be able to scale the shape any smaller. To keep the corners in proportion when you alter the size of your shape, click on the Transform Corners box at the bottom of the Transform panel.

Scaling a shape larger with Scale Corners checked will keep the corners scaled in proportion to the object. Scaling a shape larger with Scale Corners unchecked will keep the corners a set size while the shape gets larger. This may change the look of the shape because the corners will remain a fixed size.

To change from the Rounded corner style to the Inverted Round or the Chamfer, 
Option+click on the target. Each Option+click will cycle through to the next style. Option+click will also open the Transform panel where the corner options are available. To edit a single corner, double-click on the target to change it into a donut. The corner widget will be isolated from the rest of the corners and can now be pulled independently. Once you release the donut, it will turn back into a target and no longer be independent unless you double-click on it again. Corners can be selected with the Direct Selection tool to one or more corners.

Corner options are in the Rectangle Properties section of the Transform panel. The corner options are available in the dropdown menu next to each corner. The radius of the corners can be edited independently if the link icon is unlinked. If the link is selected, the corner radius will be in sync but the corner styles will still be independent of each other. To return the corners to their default (square) corner, set the value of the corner to zero.

The Direct Selection tool can be used to select and edit individual corners. You can click and drag the Direct Selection tool over the corners to activate them or click on one corner, then Shift + click on more corners to select them.

When selecting a Polygon with the Selection tool, only one corner widget will appear.

By clicking on the target and pulling it in toward the center of the shape, all the corners will round at the same radius. If you select the polygon with the Direct Selection tool, all the corner widgets will appear. You can click and drag the Direct Selection tool over the corners to activate them or click on one corner, then Shift + click on more corners to select them.

When selecting a star with the Selection tool, no corner widget will appear, and all you see is the bounding box. Stars have corners and corners have corner widgets, they just don’t show on a star unless you select it with the Direct Selection tool.

Click on the star with Direct Selection tool and all the corner widgets will appear. Pull the targets in toward the center of the shape and the corners will round with the same radius. If you pull the corner widgets in about halfway between the pointed ends and maximum widgetness, you will create a rounded-corner star. Hold Option and click on any target to change all the corners to the Inverted Round corner to create a very different shape. Option+click once more and all the corners will change to the Chamfer sides—you've just created a gear. You can click and drag the Direct Selection tool over the corners to activate them or click on one corner, then hold Shift and click on more corners to select them.