Radius/Fillet

Quick Reference: Radius/Fillet

Rounds over sharp corners, takes a round bite out of a corner, or removes an existing radius.

Location

Modifiers Toolbar

Use the Radius Tool to fillet (round over) sharp corners, take a round bite out of a corner (using a negative radius value), or turn a radius back into a sharp corner (remove a radius).

You can use Radiuses to:

Round out corners for a softer appearance
Create smooth transitions between sharp lines
Form more complex shapes (varying sizes and types)
Add rounded details to projects
Round out corners of tabs, to enable easy assembly

Using the Radius Tool¶

You can apply a radius to any corner node of any Ungrouped path or Primary Shape, provided that the lines on either side of the node can accomodate the size of the radius. Radiuses can be applied to text if you first convert it to paths.

Add a Radius to a Path¶

To add a radius, first click the Radius Tool icon in the Modifiers Toolbar.

Set the radius value to the size of the radius you wish to create — there must be enough room between the corner and nearby points to accomodate this value.

If you change the radius to a negative number it takes a fancy little bite out of the corner.

Select the object you want to modify, and click on a corner to apply the radius.

To exit the Radius Tool, press Esc on your keyboard.

When the Radius Tool is active, the icon changes as you hover over a corner to indicate whether the Radius Tool can be used. If it can't be used, the cursor will change to indicate that there is not enough space.

Icon	Meaning
	Click to fillet corner
	Click to remove fillet
	Can't fillet — not enough space

Remove or Change a Radius¶

You can also use the Radius Tool to remove rounded corners (returning them to a sharp one) by clicking on them. This even works on imported designs that were made in different software, as long as the software exported actual arcs.

After removing a radius, you can then apply a differently-sized one to the corner, as normal.

Adding a Radius to a Rectangle¶

You can apply radiuses to Rectangles in the Shape Properties Window. This method has the advantage that resizing the rectangle won't change the size of the radius, allowing you to maintain consistency in a design.

Rectangles also have a handle that acts as a shortcut for the Radius value. With a Rectangle selected, hold Ctrl / Cmd, and a blue corner radius control will appear. Drag the blue handle away from the corner to increase the radius of all four corners, and drag back toward the corner to decrease it. Dragging vertically creates a reversed radius, with a bite taken out of the corner.

Troubleshooting¶

The Radius Tool cannot be used with Grouped shapes. Ungroup any shapes you'd like to apply a radius to.
If the cursor isn't appearing as you hover over a corner, make sure you've selected the Radius Tool in the Modifiers Toolbar. The Radius icon should be highlighted. Also check that you have selected the object you wish to edit by clicking on it.
Radiuses can only be applied where there is room for the radius to be applied. If you see the following icon, it means there is not enough room:
If a radius still can't be applied, it might be because the two lines that make up the corner aren't actually joined at that point. To check, move the corner using the Edit Nodes tool. If it splits off into two lines, bring the one you moved back toward the other so that they snap together and join, and then try the radius again.
If you are having trouble converting a rounded corner back into a sharp one, it could be because there is not a true arc at the corner. This is most common with imported shapes, because some programs export arcs as a series of tiny lines. You can try recovering the arcs with Optimize Selected Shapes.

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