How to Cut Circles in Drywall

Lay out the circle's center-point placement on the drywall, using a tape measure to measure from each wall to the center of the circle. Place a pencil mark at the circle's center point on the drywall, using the tape measure as a placement guide.

Measure the diameter of the circle-shaped object the drywall surrounds with a tape measure. Divide the diameter in half, finding the circle's radius.

Turn a drywall circle cutter's thumbscrew counterclockwise until the circle cutter's arm moves freely. A drywall circle cutter looks similar to a compass, but instead of holding pencil lead like a compass, the drywall circle cutter holds a razor blade. The numbers on the circle cutter's arm represent the radius of the circle.

Adjust the drywall circle cutter's arm until the arrow below the thumbscrew points to the hole's radius measurement. The number on the arm below the arrow equals the circle cutter's radius. Tighten the circle cutter's thumbscrew.

Push the drywall circle cutter's center pin, the pin below the thumbscrew, into the pencil mark on the drywall that represents the center of the circle hole. Many circle cutters have a long center pin that completely penetrates the drywall.

Hold the drywall circle cutter's center point against the drywall and rotate the circle cutter's blade across the drywall's surface. The circle cutter's blade will cut the drywall's paper skin, exposing the drywall's gypsum core. Remove the drywall circle cutter.

Hold the blade of a drywall saw against the circle cutter's outline and push the blade through the drywall. Cut out the drywall circle with the drywall saw, following the circle cutter's outline.