How the Cabinet Door Cut List works

A frame-and-panel door is two stiles running the full height, two rails fitted between them, and a panel that floats in a groove cut into the inside edge of all four. Three sizes follow from that, and all three start from the finished door size.

Door size from the opening

Rockler's example puts a 1/2" overlay on an 11" × 22" opening and gets a 12" × 23" door. Eagle Woodworking's measuring guide gives the same rule, the inset rule with a 1/8" gap, and the pair rule: a 30" opening with a 1/2" overlay and 1/8" between the doors makes two doors 15 7/16" wide. For an inset pair this tool applies the same split to the inset width; none of the sources prints an example of that case, so it is tested as a hand-worked one.

Stiles and rails

The rails only show between the stiles, but each end also carries a short tenon (the coped end) that sits inside the stile. Leave it out and the door comes out narrower than planned by twice the tenon length. Rockler, Freud, CMT and infinitytools.com all state this rule for router-cut cope-and-stick doors and each works an example: 12" − 4 1/2" + 3/4" = 8 1/4" in Rockler's. The length to add depends on the bit set. Rockler and Freud show the tenon as long as the groove is deep (3/8" and 13/32"); CMT gives 7/16" for its tenon and infinitytools.com 7/16" for its profile width. Measure yours on a test cut.

A flat-panel shaker door made on the table saw is the same geometry: a groove along the inside edge of all four pieces and a tongue (stub tenon) on each rail end that fills it. DIY Montreal works it for a 16" door with 2" stiles and 3/8" tongues, 16" − 4" + 3/4" = 12 3/4", and MWA Woodworks for a 20" door with 1/2" tongues, 20" − 4" + 1" = 17". Both are among the tested examples below.

Panel

The panel is the opening inside the frame, plus what reaches into the groove on each side, less a gap so a solid-wood panel can swell without pushing the frame apart.

Two ways the sources write the panel width

Rockler and CMT say to make the panel 1/4" narrower than the rail is long. Freud works from the groove depth instead: door width, minus both stiles, plus both groove depths, minus the allowance. These are the same formula whenever the tenon is as long as the groove is deep, which is what a cope-and-stick bit set cuts, because the rail then reaches exactly as far into the stile as the panel could. They differ only if you enter a longer tenon for a mortised joint. This tool uses the groove form, so the panel stays right in that case, and takes tenon length and groove depth as separate inputs. With both at 3/8" and a 1/8" gap it reproduces Rockler's numbers.

The sources do not agree on how much room to leave, so the gap is yours to set:

The gap boxes in this tool are per side, so half of these totals. Freud's reason for the smaller figure along the length is that wood moves more across the grain than along it, which is also why the tool warns whenever the side gap is zero and only notes a zero gap at the top and bottom. The tool starts with Rockler's 1/8" per side all round; use the optional top-and-bottom box to set the two directions separately.

Rounding

The calculation itself is not rounded. The cut list is shown in sixteenths of an inch, or to 0.1 mm. A size that falls exactly on a 1/32" or 1/64" is shown as that fraction. Anything else is marked ≈ and rounded, by these rules:

• The listed parts are the figures to work from. The door size shown is what those parts make: rail length, less the tenon at each end, plus both stile widths, all as listed. The line under the table shows that sum, and it always adds up.
• Stile and rail widths and the tenon are echoed to the nearest step. The rail length is then worked out for those listed stiles, so the door comes out within half a step of the size asked for.
• The panel is always rounded down, and never listed larger than the space between the grooves of the frame as listed, less the gap you asked for. A list followed to the letter cannot give a panel that will not go in.

Sizes typed in millimetres rarely land on a sixteenth; switch the cut list to millimetres for those.

Guards against typing slips

Two inputs are refused because they are almost certainly mistyped, not because any source sets a limit: an opening read as more than 120 in (10 ft), which is what millimetres typed without "mm" look like, and an overlay as large as the opening itself. A side gap under 1/32" is flagged, because that is less than the smallest allowance in any of the sources.

What this tool does not cover

One rectangular door, or one pair, with straight rails and a single panel. It does not size arched or cathedral rails, mitred frames, slab doors, glass doors or doors with a centre rail, and it does not place hinges. Rockler's panel-length example is for a 4" arched top rail; it is tested here as a hand-worked case, with the 2" its arch leaves at the crown entered as a straight top rail width. The tool's own starting values use a straight 2 1/4" top rail instead, so its panel is 19" long where Rockler's is 19 1/4".

This tool cannot be published unless it reproduces every example below. 9 are copied from a published source. 8 were worked by hand from the cited rule.