What size cabinet door do you need?
Enter the opening, get the door size to the 1/16 inch instantly.
The overlay comes from your hinges — see their spec sheet.
How do I size an overlay cabinet door?
Add the overlay twice to the opening — once for each side. A 15 × 30 inch face-frame opening with a ½ inch overlay needs a 16 × 31 inch door.
How do I size a pair of cabinet doors?
Add the overlay to both sides of the opening, subtract the gap between the doors and split what is left in two. A 30 inch opening with a ½ inch overlay and a ⅛ inch gap: (30 + 1 − 0.125) ÷ 2 = 15 7/16 inches for each door.
How do I size an inset door?
Inset doors sit inside the opening, so subtract a small reveal on each side instead. With a 1/16 inch reveal, a 15 × 30 inch opening takes a 14 7/8 × 29 7/8 inch door.
How much overlay should I use?
The hinges decide it. Face-frame cabinets often use a ½ inch partial overlay; frameless (European) cabinets use full-overlay hinges that cover nearly all of the box edge. Check the overlay on your hinge's spec sheet before ordering doors.
Does this work for drawer fronts?
Yes. A drawer front is sized like a single door: the opening plus the overlay on each side. Leave a gap between a drawer front and the door below it the same as between two doors.
What is the difference between overlay and inset doors?
An overlay door sits in front of the cabinet and covers part of the frame or box around the opening. An inset door sits inside the opening, flush with the frame, so it needs a small clearance on every side and must be made more precisely.
What if the opening is not square?
Measure the width and height at several places. If they differ by more than 1/16 inch, the overlay will vary along the edge. Check the opening with a square before you order, and use the hinge's adjustment range to make up small differences.
How the calculation works
For an overlay door, each side of the door extends past the opening by the overlay, so the door is the opening plus twice the overlay in both width and height. For an inset door, the door is the opening minus twice the reveal (the clearance on each side). For a pair of doors, the full width is worked out first, the gap between the two doors is subtracted, and the rest is divided by two. All sizes are rounded to the nearest 1/16 inch to match how doors are ordered.
Worked examples
Take an opening 18 inches wide and 30 inches high. With a ½-inch overlay, the single door is 19 by 31 inches (18 + 1 by 30 + 1). With a larger 1¼-inch overlay for a frameless cabinet it is 20 1/2 by 32 1/2 inches. As an inset door with a 1/16-inch reveal, it is 17 7/8 by 29 7/8 inches. For a pair of doors on a 33-inch opening with a ½-inch overlay and a ⅛-inch gap, the combined width is 33 + 1 = 34 inches; take off the gap to get 33⅞, and each door is 16 15/16 inches wide and 31 inches high.
Common mistakes
- Ordering doors before choosing the hinges. The hinge sets how much overlay a door can have. Check the hinge specification first.
- Ignoring the gap between a pair of doors. Two doors that each cover the full overlay will collide in the middle. The gap must be taken out of the combined width.
- Mixing up opening and cabinet size. The opening is the clear space you can see through. The outside of the cabinet or face frame is larger and is not what the formula uses.
Sources and related calculators
Method: standard door-sizing arithmetic for overlay and inset cabinet doors; actual overlay values come from the hinge manufacturer's specifications. Related: drywall calculator, baseboard calculator and wainscoting calculator.