Calculate finished cabinet door dimensions for overlay-style mounting.
Overlay & reveal reference
| Type | Overlay / side |
|---|---|
| Full overlay | 1/2 in |
| Partial overlay | 3/8 in |
| Inset | 0 (reveal instead) |
| Reveal / gap | Recommended |
|---|---|
| Inset reveal | 1/16 to 1/8 in |
| Pair center gap | 1/8 in |
Usage Tip
Confirm your hinge style; full-overlay, half-overlay, and inset hinges each change how much the door should cover.
door height = opening height + 2 × overlay
paired door = (door width − gap) ÷ 2
The single-door size is shown; the pair figure is each of two doors.
The real question: what size door do I actually build?
Most people reach for a cabinet door calculator thinking the hard part is the math. It is not. The math is simple addition. The hard part is knowing which measurement to add and which style of cabinet you are building. Get the style right and the door size falls out automatically. Get it wrong and you are looking at a freshly machined piece of hardwood that is exactly 1/8 in too small — useless, and not cheap to replace.
This tool starts from the decision you are actually making: overlay or inset, single door or a pair, cabinet door or drawer front. Tell it the opening and the style, and it returns the finished door size, the reveal, and a diagram so you can sanity-check before you cut.
Overlay vs inset: the difference that changes everything
There are two fundamental ways a door relates to its opening.
Overlay doors
The door sits on top of the cabinet face and is larger than the opening. You add an overlay to each side. Door width = opening width + 2 x overlay. This is the most common style in modern kitchens.
Inset doors
The door sits inside the opening, flush with the face frame, with a small even gap (the reveal) around it. The door is smaller than the opening. Door width = opening width − 2 x reveal. Inset is the traditional, furniture-grade look and is far less forgiving of error.
Face frame vs frameless (Euro): which do you have?
This trips up more DIYers than any other point, so it is worth being clear.
Face frame cabinets have a solid wood frame attached to the front of the box. Doors mount to that frame. Overlay is measured against the frame opening, and you have room for partial or full overlay, or true inset.
Frameless (also called Euro or full-access) cabinets have no front frame — the door covers the box edge directly. These almost always use full overlay with concealed Euro hinges. There is no inset option on a frameless box.
Full overlay vs partial overlay
Within overlay construction, how much the door covers the frame is the overlay amount per side.
| Cabinet type | Typical overlay per side | Look |
|---|---|---|
| Full overlay | 1/2 in (1/2 to 5/8 in common) | Doors nearly touch; minimal frame showing |
| Partial overlay | 3/8 in (3/8 to 1/2 in common) | Frame visible between doors; budget-friendly |
| Inset | 0 (uses a reveal gap instead) | Door flush inside frame; furniture grade |
The values above are practical defaults. Always confirm the overlay your hinges are rated for before cutting — the hinge, not the calculator, sets the limit.
Single door or double doors: when to split an opening
A rough rule of thumb: openings up to about 24 in wide take a single door; wider openings get a pair so each door does not sag, warp, or swing into the next cabinet. For a pair, the two doors share the opening with a small center gap between them.
Combined door width = opening width + 2 x overlay. Each door = (combined width − center gap) / 2. The tool handles the split for you and shows both the each-door size and the pair total.
Drawer fronts follow the same rules
A drawer front is just a short, wide overlay (or inset) panel. The same formula applies: front width = opening width + 2 x overlay, front height = opening height + 2 x overlay. Drawer fronts are always single panels, so there is no pair mode — switch the tool to Drawer Front and it adjusts.
Reveals and gaps: getting the spacing right
The reveal is the visible gap — between a door and the frame edge (inset), or between two doors of a pair (overlay). Consistent reveals are what separate a clean install from an amateur one.
| Gap | Recommended | Where |
|---|---|---|
| Inset reveal | 1/16 to 1/8 in | All around an inset door |
| Pair center gap | 1/8 in | Between two overlay doors |
| Door-to-door (stacked) | 1/8 in | Between a door and a drawer above it |
Hinges and how they affect your door
Hinges do not change the door size, but they decide whether your chosen overlay is even buildable, so pick the hinge and the style together.
Concealed Euro hinges are the standard for full-overlay and frameless doors; they need a 35 mm cup bore near the edge. Soft-close is a feature available on most Euro hinges, not a separate size. Inset hinges (or traditional butt/barrel hinges) are required for inset doors — a standard overlay hinge will not sit a door flush inside the frame.
Common cabinet opening and door sizes
Finished door sizes for typical openings at 1/2 in full overlay (single door). Adjust for your actual overlay.
| Opening (W x H) | Door size (full overlay) | Door size (inset, 1/16 reveal) |
|---|---|---|
| 12 x 30 in | 13 x 31 in | 11-7/8 x 29-7/8 in |
| 15 x 30 in | 16 x 31 in | 14-7/8 x 29-7/8 in |
| 18 x 30 in | 19 x 31 in | 17-7/8 x 29-7/8 in |
| 24 x 30 in (pair) | two at 12-7/16 x 31 in | two at 11-5/16 x 29-7/8 in |
| 30 x 30 in (pair) | two at 15-7/16 x 31 in | two at 14-5/16 x 29-7/8 in |
| 36 x 30 in (pair) | two at 18-7/16 x 31 in | two at 17-5/16 x 29-7/8 in |
Five ways to avoid the 1/8 in mistake
1. Measure the actual opening, not the box — and measure each opening, since they vary. 2. Confirm overlay vs inset before you touch a saw. 3. Match your hinge to the style first. 4. Cut one test door from scrap and dry-fit it. 5. Keep reveals consistent across the whole run, not just one cabinet.
Frequently asked questions
How much bigger than the opening should an overlay door be?
Add your overlay to each side. At 1/2 in full overlay, the door is 1 in wider and 1 in taller than the opening. At 3/8 in partial overlay, it is 3/4 in larger in each direction.
How much smaller should an inset door be?
Subtract twice the reveal. With a 1/16 in reveal, the door is 1/8 in smaller than the opening in both width and height; with 1/8 in reveal, 1/4 in smaller.
When should I use two doors instead of one?
Generally once an opening passes about 24 in wide. A pair keeps each door from sagging on its hinges and from swinging awkwardly far into the room.
Do drawer fronts use the same overlay as doors?
Yes. Use the same overlay amount so the gaps line up across the whole cabinet face. Switch the tool to Drawer Front mode and it applies the identical formula.
What is the difference between face frame and frameless?
Face frame cabinets have a wood frame on the front that doors attach to; frameless (Euro) cabinets do not, so the door covers the box edge directly. Frameless is full overlay only; face frame can be partial, full, or inset.
Does the hinge change the door size?
No, but it limits which overlays are possible and whether an inset door will sit flush. Choose the hinge to match the style before finalizing the size.
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Estimates are provided for planning and educational purposes. Always dry-fit a test piece and confirm overlay against your specific hinge hardware before cutting final material. Verify all measurements against your actual cabinet openings.