MachineCalcs

Cabinet Door Size Calculator

Size overlay or inset cabinet doors from the measured opening, reveal or overlay allowances, and optional paired-door center gap. Built for door-slab cut sizes before hinge boring or shop-specific hardware details.

Materials 12 inputs 9 results
Used in Woodworking 25

Calculator

Inputs

View results
Overlay doors cover past the opening. Inset doors fit inside the opening with a reveal around the edges.
Measured cabinet opening width before applying overlay or inset reveals.
in
Measured cabinet opening height before applying overlay or inset reveals.
in
Door coverage beyond the opening on the left side.
in
Door coverage beyond the opening on the right side.
in
Door coverage beyond the opening at the top.
in
Door coverage beyond the opening at the bottom.
in
Gap between the two doors in a paired opening.
in

Results

Default result
Edit inputs
Door width(W_door)
15.438in
Pass

each of two doors

Also computed

Door height(H_door)Pass25in

overlay pair

Door count(N)2doors

Total slab width(W_total)30.875in

two slabs, gap not included

Center gap used(G_c)Pass0.125in

between paired doors

Net width adjustment(dW)1in

net overlay: added to the opening before splitting paired doors

Net height adjustment(dH)1in

overlay added vertically

Cabinet door preview: overlay pairCabinet door sizing previewoverlay pairOpeningDoor eachTotal door width plus center gapcenter gapPreview shows the sizing convention only; hinge bore, edge profile and out-of-square correction are separate shop decisions.
Method notes 4 notes
  • door width each = (opening width + left overlay + right overlay - center gap) / 2
  • door height = opening height + top overlay + bottom overlay
  • Paired doors split the net slab width after subtracting the center gap. The center gap itself is not part of either door slab.
  • Confirm hinge overlay, cup bore location, pull clearance, edge profile, finish thickness and out-of-square openings before cutting finished doors.

Cabinet door sizing starts from the finished opening. Overlay doors add left/right and top/bottom overlay to the opening; inset doors subtract left/right and top/bottom reveals. For paired doors, the center gap is subtracted before the width is split equally. This calculator returns the per-door width, height, door count, total slab width and door area for cut-list or sheet takeoff planning.

Continue workflow

All Materials
Workflow placement Woodworking Stage 2: Build cabinet parts
Next 1 Size drawer box Size drawer boxes for the same cabinet opening workflow before building a drawer cut list. Next 2 Size drawer slides Size drawer slide clearance and length when the same opening includes hardware-guided drawer boxes. Next 3 Optimize sheet cuts Pack repeated plywood, MDF, OSB or melamine rectangles into full sheets with kerf, edge trim, rotation, yield, cost and a layout preview. Chart Use reference data Decimal to fraction chart

How to use this calculator

  1. Choose the layout. Select overlay or inset, and single door or paired doors.
  2. Measure the opening. Enter the finished cabinet opening width and height after face-frame or casework work is complete.
  3. Enter overlay or reveal. For overlay doors, enter the door coverage beyond the opening. For inset doors, enter the visible reveal gaps.
  4. Set the center gap. For paired doors, enter the gap between the two doors before reading the per-door cut size.

How it works

Cabinet door sizing starts from the finished opening. Overlay doors are larger than the opening, so the calculator adds the left and right overlay to the width and adds the top and bottom overlay to the height. overlay door width = opening width + left overlay + right overlay

Inset doors fit inside the opening, so the reveal is subtracted instead: inset door width = opening width - left reveal - right reveal For paired doors, the center gap is subtracted from the total slab width before the result is divided by two.

If the face frame itself is not settled yet, start with the cabinet face frame opening calculator. After the outside door size is known, move into the cut list calculator for rails, stiles or linear stock, the plywood sheet calculator for sheet-goods area, and the shelf sag calculator when the same cabinet also has loaded shelves.

Worked example

Verified against the live calculator

A paired overlay opening is 30 in wide and 24 in tall. With 1/2 in overlay on the left and right and a 1/8 in center gap, the total slab width is 30 + 0.5 + 0.5 - 0.125 = 30.875 in. Each door is 15.4375 in wide. With 1/2 in top and bottom overlay, the door height is 25 in.

Frequently asked questions

How do I calculate cabinet door size for overlay doors?

Add the left and right overlay to the opening width. For a pair of doors, subtract the desired center gap and divide the remaining slab width by two. Add the top and bottom overlay to the opening height.

How do I calculate inset cabinet door size?

Subtract the left and right reveals from the opening width. For a pair of inset doors, subtract the center gap as well and divide by two. Subtract the top and bottom reveals from the opening height.

What center gap should paired cabinet doors use?

A small reveal such as 1/8 in is common, but the right value depends on hinges, door pull style, finish thickness, humidity movement and how square the opening is.

Does this include hinge cup boring or hardware placement?

No. This calculator sizes the door slab from the opening, overlay or reveal, and center gap. Hinge cup diameter, bore offset, hinge overlay rating, pulls and edge profiles are hardware-specific shop layout steps.

Can I use this for slab, shaker or raised-panel doors?

Yes for the outside door size. Rail, stile, panel groove, cope-and-stick profiles and floating-panel clearance need separate joinery or cabinet-shop calculations.

Method & assumptions

  • Opening dimensions are finished, measured dimensions, not nominal cabinet or face-frame dimensions.
  • Overlay sizing adds side/top/bottom coverage; inset sizing subtracts side/top/bottom reveals.
  • For paired doors, the center gap is subtracted before splitting the remaining slab width equally.
  • The result is the outside door slab size only. Hinge cups, bore offsets, edge profiles, door stops, pulls, finish thickness and out-of-square correction are not solved here.
  • Wood movement, frame-and-panel clearance, glass retainers and shop-specific standard reveals still need the cabinetmaker's layout rules.
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