Kitchen Cabinet Calculator

How the kitchen cabinet calculator works

Kitchen cabinets come in a set of standard widths, so planning a run is a matter of fitting whole boxes along a wall and dealing with what is left at the end. The calculator does that for the base cabinets under the countertop and, if you want them, the wall cabinets above. For each run it counts how many cabinets of your chosen width fit, then looks at the leftover gap: if a narrower standard cabinet fits into it, that cabinet is added; if not, the gap is closed with a filler strip.

Full-width cabinets N = ⌊L ÷ w⌋, where L is the run length and w the cabinet width, and the gap left over is L − N × w. The total is the base and wall cabinets together, and the estimated cost is that count times the price per cabinet you enter.

Measure the runs, not the walls

The run length is the wall space that actually gets cabinets. Leave out the spaces for a freestanding range or cooker, the fridge and a dishwasher, and measure each straight run separately. The wall cabinet run is usually shorter again, because the window, the cooker hood and any open shelving take space, which is why it has its own input. Leave it equal to the base run if the two match. If you would rather start from the whole wall, the cabinet run planner takes the appliance spaces out for you. Where two runs meet at a corner, one of them carries a corner cabinet, so plan the corner first and measure the remaining straight lengths from its edge.

Standard cabinet widths

In the US, KraftMaid's cabinet size guide lists base and wall cabinets from 6 in wide up to 48 in in 3 in steps, with base cabinets 24 in deep and 34 1/2 in tall, which with a 1 1/2 in countertop gives the standard 36 in working height. Wall cabinets are 12 in deep and usually hung 54 in above the floor, 18 in above the countertop, so a 42 in tall wall cabinet reaches an 8 ft ceiling. The calculator uses that 3 in series for the gap: any gap of 6 in or more gets the widest cabinet in steps of 3 in that fits, and whatever is left becomes filler.

Europe works to the coordinating sizes in EN 1116, which CATAS summarises in its overview of the 2018 edition: nominal base-unit widths of 400, 500, 600 and 900 mm, the widths it uses for units housing appliances, and worktop heights of 850, 900 or 950 mm. UK ranges add other widths; Howdens, for example, lists 350 mm and 450 mm units alongside the usual 600 mm. On the metric side the calculator fills a gap with the widest of 900, 600, 500, 450, 400 or 350 mm that fits. Smaller gaps are flagged for a narrow unit, if your range has one, or a filler.

A worked example

Take a 13 ft base run with 24 in cabinets. 13 ft is 156 in, and 156 ÷ 24 = 6.5, so six full cabinets fit with 12 in left over. A 12 in cabinet fills that exactly, so the run takes seven base cabinets and no filler. With a matching wall run the total is 14, and at $220 a cabinet the estimate is $3,080. On the metric side, a 4 m run of 600 mm units takes six with 400 mm spare, which a 400 mm unit fills: seven base units, fourteen with the wall run, £2,520 at £180 each.

Change the wall run to 7 ft with 30 in wall cabinets and the wall count becomes two full cabinets (60 in) plus a 24 in one for the remaining 24 in. An 8 ft 2 in base run of 24 in cabinets leaves 2 in, too narrow for any cabinet, so it shows as a 2 in filler.

Fillers and end panels

A small filler is normal and useful: one at each end of a run, next to a wall, lets doors and drawers open past the handles of the cabinet beside them and hides a wall that is not quite straight. Fillers are usually cut to size on site from a matching strip, so a gap narrower than the smallest cabinet in the range is simply taken up with filler. A larger leftover is better filled with a narrow cabinet for trays or spices. Exposed cabinet sides at the end of a run need an end panel in the door finish, and they are ordered separately.

Mixing widths

The calculator assumes one width for each run, which suits a quick count and a budget. A real design mixes widths: a 36 in or 900 mm sink base, a drawer stack beside the cooker, a narrow pull-out. If you know the sink base width, subtract it from the run, count the rest here, and add the sink base back. The count will not change much, but the cabinets will line up with the plumbing and appliances.

What this tool does not do

It does not count corner cabinets, tall pantry or oven housings, end panels, plinths, cornice or handles, and the price is a flat price per cabinet, when wide and specialist cabinets cost more. Cabinets must be fixed to the wall as the maker specifies, into studs or with fixings rated for the load, and any new sockets, lighting or plumbing need a qualified trade.

Using this with other BuildMetricLab tools

The countertop calculator works out the worktop for the same run, the appliance cutout calculator the openings for built-in appliances, and the backsplash calculator the tiles or panels between the countertop and the wall cabinets. All BuildMetricLab tools run in your browser with no sign-up, and the formula is on the page so the maths can be checked.