Creating Quarter-Circles in Adobe Illustrator

Here’s a quick way to draw a quarter-circle in Adobe Illustrator. It involves using just one tool: the arc tool.

These instructions will work in Adobe Illustrator from CS–CS5.

How to create a quarter-circle (or quarter-ellipse) in Illustrator

1. Select the arc tool. (Click and hold the straight-line–segment tool to bring up the sub-menu of additional line-segment tools)
2. Use the arc tool to make your quarter-circle:

   A. Freehand method

   Before drawing a freehand quarter-circle for the first time, you must use the exact-size method to enable closed-shape drawing. If you do not, you will only get the curved line, not the whole the shape.
   Quarter-circle: Hold down the shift key on your keyboard, click and drag to draw a quarter-circle of the desired size.
   Quarter-elipse: Click and drag to draw a quarter-elipse of the desired size.

   B. Exact-size method

   Click once anywhere on your artboard to open the arc tool options dialogue.

   

   Type in your desired dimensions for the radius of your quarter-circle, and select Closed from the Type drop-down. If your y-axis and x-values are equal, you will be drawing a quarter-circle, but if they differ, you will draw a quarter-ellipse.

   Click ok.

3. Success. You now have a quarter circle. You can change the fill, size, stroke, etc as with any other shape.