IKEA doors are designed to fit properly in front of each cabinet. If the door is too long, or if you wish to repurpose the cabinet door for another piece of cabinetry or project, cut the door to the proper size using a few tools. When cutting down the IKEA cabinet door, be careful not to cut too much. It is more difficult to extend the cabinet door than to trim it.
Place an old blanket or towel over a set of sawhorses. This will protect the IKEA cabinet door from the sawhorses.
Unscrew the IKEA cabinet hinge from the frame with a Phillips screwdriver. If cutting along the hinge side of the cabinet door, remove the hinges from the door as well. Set the door, upside down, on the two sawhorses.
Place a scribe line on the IKEA cabinet with a pencil. Draw a straight line horizontally or vertically across the door to represent the portion that needs to be cut after measuring and marking the part to be cut off with the measuring tape.
Set a level along the line to verify it is plumb.
Line masking tape or painter's tape just beside the line to protect the cabinet finish from the circular saw. The tape must be on the side of the line where the body of the circular saw will sit.
Place a plank or piece of scrap wood on the other side of the line to use as a guide. Use two clamps to hold the guide to the door.
Plug in the circular saw. Place the saw blade right on the line. Hold the saw handle with one hand, then use medium pressure to guide the saw along the cut line on the cabinet door.
Remove the tape from the cabinet door.
Sand the cut edge of the door with medium-grit sandpaper. The IKEA cabinet door is now cut. You can now prime and paint, or stain the cut edge if necessary.