Select the shape you want to round corners on. In the top main menu, click Effect > Stylize > Round Corners. Choose the radius for the curve that you want and click OK. You can also use the Direct Selection Tool to round corners by clicking and dragging the corners.
My name is April, and I’ve been working in the graphic design field for 13+ years now. Adobe Illustrator offers many ways to create imagery. The various shape tools will let you easily create a shape and then you can use tools to modify the shapes.
In this tutorial, I’m going to show you two quick ways to round corners in Adobe Illustrator. Let’s look into our options.
Note: The screenshots from this tutorial are taken from Adobe Illustrator CC Windows version.
Table of Contents
Follow the steps below to use the Stylize option for rounding corners.
Step 1: Select the shape that you want to round corners. Use the Selection tool so the entire shape is selected. I am going to use a star for this example.

Step 2: Go to the main menu Effect > Stylize > Round Corners.

Step 3: This will bring up the Round Corners dialog box. You will need to choose a radius for the rounded corners. As you change the measurements, you will see them change because of the preview being checkmarked.

For example, I played around with the radius and I am going to choose 0.25”. You can see the blue lines that indicate where the previous edge was.

If you want to make the change permanent, go to Object > Expand Appearance.

Now the corners are officially rounded.

Method 2: Round Corners with Live Corners
Round corners manually is another option, and you can use the Direct Selection Tool to do so.
Step 1: Use the Direct Selection Tool to select all of the anchor points you want to round. If you want to select multiple corners, click and select, hold the Shift key to select multiple shapes.

Step 2: If you hover over the anchor point, you will see the symbol change. Click and drag to round the corners.

When you release, the corners will appear rounded.

Step 4: Unless you expand them, you can change one or more corners the same way since they are live corners.

Note: You can even round live corners when the shape is being used as a clipping mask.

Final Thoughts
Rounding corners can be a nice aesthetic change for your shape and help you design something with round edges. If you are better with measurements then using the Stylize menu will work great. If you want to use the Live Corners, you can view how the edges look as you change them.
Have you tried rounding corners in Illustrator? Which method did you prefer to round corners? Let me know in the comments below.