Overlay is the lap past the opening onto the face frame. Enter the opening, pick 1/2, 3/4, or 1-1/4 in overlay (or an inset reveal), and get the finished door. A pair splits after a center gap. The hinge overlay rating has to match this number. This is a size calculator, not a door order.
Use it when ordering or making doors for face-frame cabinets. Measure the opening, choose the overlay your hinges give (½ in is common), and the page returns the finished door size, including a pair of doors with a gap between them.
It prevents the classic mistake of ordering doors to the size of the opening, and it keeps a whole run of doors consistent when the openings vary.
On overlay work the door is larger than the opening. Each edge hangs over the frame by the overlay amount, so width and height each pick up twice that amount. A pair still overlays the far stiles; at the meeting edge the two doors share the opening and need a small gap so they do not bind. Subtract that gap, then split. Inset is the inverse: the door sits in the opening, so you subtract a reveal on each side instead of adding overlay.
Overlay, one door: DW = OW + 2 × OL · DH = OH + 2 × OL
Overlay, pair: DWeach = (OW + 2 × OL − gap) / 2 · DH as above
Inset, one door: DW = OW − 2 × reveal · DH = OH − 2 × reveal
Inset, pair: DWeach = (OW − 2 × reveal − gap) / 2 · DH as inset
OW and OH are the inside of the opening. OL is overlay per side — the same number the hinge is sold under. A 1/2 in overlay makes a single door 1 in taller and 1 in wider than the hole. This page does not pick a cup boring, mounting plate, or door-shop SKU.
| Case | Finished door |
|---|---|
| 15 × 27 in opening, 1/2 in overlay, 1 door | 16 × 28 in |
| 30 × 27 in, 1/2 in overlay, pair, 1/8 in gap | each 15-7/16 × 28 in |
| 12 × 24 in, 1-1/4 in overlay, 1 door | 14-1/2 × 26-1/2 in |
| 15 × 27 in, 3/4 in overlay, 1 door | 16-1/2 × 28-1/2 in |
| 15 × 27 in inset, 1/8 in reveal, 1 door | 14-3/4 × 26-3/4 in |
Those five rows come from the formulas above. The 15 × 27 in opening at 1/2 in overlay is the usual shop check: add an inch each way.
Tape the inside of the face frame — left stile to right stile, bottom rail to top rail. Not the outside of the cabinet, not the door that is already there. If the hole is out of square, use the smallest width and the smallest height so the new door still clears.
Concealed cup hinges and wrap-around face-frame hinges are sold by overlay: 1/2 in, 3/4 in, 1-1/4 in, and so on. That rating is how far the door sits past the opening when the hinge is closed. Size the door for 1-1/4 in and hang it on a 1/2 in hinge, and the door lands a full 3/4 in short of where you cut it. Match the hinge to the number on this calculator. This page is not a Blum catalog and does not set cup boring or plate height.
A door maker cuts the finished width and height you send. If you quote the opening (15 × 27) they may ship a 15 × 27 door — the size of the hole, with no overlay. Send the numbers this calculator prints (16 × 28 in the shop check). Measure twice before you order; this page does not know your bumper pads, outside edge profile, or whether adjacent doors share a stile.
1/2 in partial overlay is the common US face-frame default and leaves about an inch of frame showing around a single door. 1-1/4 in full overlay is the usual match for a 1-1/2 in face frame and leaves about 1/4 in of frame. 3/4 in sits in the middle — it still needs a 3/4 in overlay hinge, not a 1/2. Type Custom if your hinge card shows something else.
One door overlays all four sides of the opening. Two doors overlay the far stiles and the top and bottom rails; they share the opening at the meeting edge. Subtract the center gap (default 1/8 in) before splitting width. Height is the same as a single door. Do not split first and then add overlay — that double-counts the meeting edge.
The door sits in the opening, flush with the frame face (or just proud, depending on the hinge). Subtract a reveal on each side instead of adding overlay. 1/8 in all around is a typical starting reveal. Use inset hinges, not overlay hinges. A pair still needs the center gap on top of the side reveals.
Yes, for overlay or inset false fronts: treat the drawer opening as OW × OH and run a single door. The drawer box is a different calculator — slides want clearance inside the case, not overlay on the face. See the drawer box calculator for that cut list.
Measure the inside of the case. Overlay is then how far the door covers the 3/4 in (or 5/8 in) side panel. Do not blindly use a face-frame 1/2 in overlay on a frameless run — the remaining reveal on the case edge is whatever is left of that panel thickness. Adjacent doors still need a gap. Hinge boring and mounting plates follow the hinge sheet, not this calculator.