If you’re looking to cut a circle in half in Illustrator CC, this super simple tutorial will show you how to use the scissors and pen tools to cut any ellipse in half in a matter of seconds.
With this simple technique, you can bring semi-circles and half-circles into your designs, complete with effects and colors, without trying to freehand flawless curves using the pen tool.
Video Tutorial
Feel free to watch my video tutorial above and learn how to apply this technique in under 2 minutes. I keep things short and to the point, and in no time at all you’ll be bringing half circles of all shapes and sizes into your designs.
Step-by-Step Tutorial
Create Circle
Step 1 – With a new document open, select the ‘ellipse tool’ from the lefthand toolbar.
Step 2 – Hold shift (for a uniform circle), then click and drag out an ellipse on the artboard.
Step 3 – Release to create the ellipse.
Step 4 – To make it easier to see the halved circle, add a fill and stroke. With the circle selected, click the ‘fill’ color in the lefthand toolbar.
Step 5 – Select a color in the ‘color picker’ menu and click ‘ok’ to apply.
Step 6 – Click the ‘stroke’ color and repeat step 5 for the stroke, then go to ‘window > stroke’ and increase the weight of the stroke.
Cut Circle
Step 7 – Select the ellipse/circle with the selection tool.
Step 8 – Select the ‘scissors tool’ from the lefthand toolbar.
Step 9 – The four anchor points of the circle will appear. To start the cut, click the anchor point on the left of the circle.
Step 10 – Now click the anchor point on the right of the circle to complete the cut. The position of the stroke will change.
Step 11 – Select one half of the circle with the selection tool, and then click and drag one half away from the other.
Complete Path
Step 12 – While the circle has, in theory, been cut in half, we now have two incomplete paths. Below I have removed the fill from one of the halves, and as you can see, the half circle is one curved path, and not a complete shape. To complete the path, first select one of the halves with the ‘selection tool’.
Step 13 – Select the ‘pen tool’ from the lefthand toolbar.
Step 14 – Hover over one of the open ends of the path, until the little diagonal line icon appears, then click to select the anchor point.
Step 15 – Hover over to the other open end of the path, and over the anchor point. A little circle (shown below) will appear when you are over the anchor point, which means you can close the path. Click to close it.
Step 16 – The path will connect, and you now have a complete shape. The alignment of the stroke may change, so go to ‘window > stroke’ and select either ‘outside’, ‘inside’, or ‘central’ under the align stroke options.
Step 17 – Repeat for the other half circle.
Using a combination of the scissors and pen tools, you can very quickly cut circles and ellipses in half in a matter of seconds. By connecting the paths back up, you can then apply a range of fill, stroke, and effects options that are only applicable to complete paths.
You can also cut plenty of other shapes using this method, and save yourself lots of time and headaches trying to get perfect 90-degree curves by using the pen tool.