Free tool for countertop shops
Countertop calculator for fabricators
Enter the pieces on a job and the slab you are cutting them from. You get finished square feet, edge in linear feet, cutout count, and how many slabs to pull.
Built for the person who prices the job. Every assumption is a box you can change, and the arithmetic is shown under the result. No account is needed.
Your piece names and sizes stay in your browser. We count when the tool is used, printed, copied or downloaded, and log totals such as pieces, cutouts, slabs to pull and whether you entered a slab cost.
Homeowner? The finished square feet and edge length are two numbers a fabricator will ask you for.
1. Slab and assumptions
All of these are yours to change. The starting values are examples, not industry figures.
Read it off the slab tag. Lot sizes vary.
Across the slab, from the tag.
Stone lost along each slab edge to chips and uneven edges. Set it to what you lose along the edges of the slabs you buy.
Blade width (kerf) plus clearance between two cuts.
Adds this percent to the piece area before the area count. It adds a slab only when that area count passes the layout count. Starts at 0.
Leave blank to skip the cost lines. We do not know your prices.
2. Finished pieces
One row per piece. Type 25.5 or 25 1/2. Take sizes from the template or shop drawing. Add a backsplash as its own piece, a long thin strip.
Piece 1
For example, Sink run or Island.
Front to back, with overhang.
Piece 2
For example, Sink run or Island.
Front to back, with overhang.
Piece 3
For example, Sink run or Island.
Front to back, with overhang.
Piece 4
For example, Sink run or Island.
Front to back, with overhang.
3. Cutouts
Use the cutout size from the sink or cooktop template. The count is per copy of the piece.
Cutout 1
Cutout 2
Your takeoff
- Slabs to pull
- 2
- The layout fits on 2 slabs. Area alone says at least 2 (1.08 slabs of usable stone).
- Finished area (net of cutouts)
- 49.44 sq ft
- Finished edge
- 48.67 LF
- Cutouts
- 2
- 7.44 sq ft of drops
- Yield
- 44.8%
- finished stone over stone bought
- Area is 1.08 slabs and you pull 2, so part of the last slab goes unused. That holds yield down.
Where the purchased stone goes
- Finished tops: 49.44 sq ft (44.8%)
- Cutout drops: 7.44 sq ft (6.7%)
- Offcuts and saw gaps: 48.18 sq ft (43.7%)
- Trim margin: 5.19 sq ft (4.7%)
Offcuts are not automatically a loss. A usable remnant is stone you can sell or use on another job.
One way the pieces fit
Drawn to scale from your sizes. Dashed line is the usable area inside the trim margin.
Piece positions in text
| Piece | From left (in) | From top (in) | Size (in) | Turned |
|---|---|---|---|---|
| Island | 1 | 1 | 72 x 40 | No |
| Backsplash strip (1 of 2) | 1 | 41.25 | 90 x 4 | No |
| Backsplash strip (2 of 2) | 1 | 45.5 | 90 x 4 | No |
Piece positions in text
| Piece | From left (in) | From top (in) | Size (in) | Turned |
|---|---|---|---|---|
| Range wall run | 1 | 1 | 96 x 25.5 | No |
| Sink run | 1 | 26.75 | 84 x 25.5 | No |
Show the math
- Piece area: 96 x 25.5 + 84 x 25.5 + 72 x 40 + 90 x 4 x 2 sq in, divided by 144 = 56.88 sq ft.
- Cutout drops: 7.44 sq ft. Finished area = 56.88 - 7.44 = 49.44 sq ft.
- Finished edge: each finished side adds its length. Front and back use piece length, left and right use depth. Inches divided by 12 = 48.67 LF.
- Usable slab: (126 - 2 x 1) by (63 - 2 x 1) = 124 by 61 in = 52.53 sq ft.
- Slabs by area: 56.88 / 52.53 = 1.08, rounded up to 2. No layout can use fewer.
- Slabs by layout: 2. Pieces packed in rows with straight cuts across, 0.25 in left between neighboring pieces.
- Slabs to pull: whichever is larger, the layout count (2) or the area count with a 0% buffer (2) = 2.
- Yield: finished area 49.44 / full area of the slabs pulled (2 x 55.13) = 44.8%.
Planning estimate, not a cut plan. This does not see defects, veining or bookmatching. Confirm the count on the slab before you buy or cut.
How the numbers work
- Piece area. Length times depth, divided by 144, times the quantity. A square foot is 12 in by 12 in, which is 144 sq in.
- Cutouts. Length times width, divided by 144. The drop stays inside the piece rectangle, so it lowers finished area but not the room the piece takes on the slab.
- Finished edge. Each finished side adds its length. Front and back use the piece length. Left and right use the depth. Total inches divided by 12 gives linear feet.
- Usable slab. Slab length minus two trim margins, by slab width minus two trim margins.
- Slabs by area. Total piece area divided by usable slab area, rounded up. This tool counts every rectangle whole, so no layout it draws can use fewer.
- Slabs by layout. Pieces are lined up in rows with straight cuts across the slab, and your gap is left between neighboring pieces. A piece may be turned 90 degrees unless you tell the calculator not to. It tries eight ways of lining the pieces up and keeps the one that uses the fewest slabs.
- Slabs to pull. Whichever is larger: the layout count, or the area count with your re-cut buffer added to the piece area.
- Yield. Finished area divided by the full area of all the slabs pulled.
- Cost per finished square foot. Only if you enter a slab cost: slabs pulled times slab cost, divided by finished area.
Unit source: the foot is defined as exactly 0.3048 meter (NIST and NOAA National Geodetic Survey, Federal Register 85 FR 62698, 5 October 2020, PDF). An inch is one twelfth of a foot, so a square foot is 144 square inches. Areas, edge and yield are arithmetic on the numbers you type. The slab count comes from a routine that tries eight ways of laying the pieces out, and it can miss a tighter fit. The starting slab size, trim and gap are examples. There are no built-in prices, rates or industry averages.
What this does not know
This is a planning estimate, not a cut plan. It handles rectangles only. Waterfalls, miters, seam placement and L-shapes are not modeled. Enter each waterfall leg, return or L-shape arm as its own rectangle, and add miter allowance and edge by hand. Defects, veining and bookmatching are decided on the slab.
It prices only the slab, and only if you enter a cost. Edge and cutout rates, labor, install, tax and tear-out belong in your quote.
Taking off a job in five steps
- Measure each straight run on its own. Add an island or peninsula as its own piece.
- Use the depth from the template or shop drawing, including overhang.
- Mark the sides that get a polished or profiled edge. Skip sides against a wall.
- Add each cutout from its template. Use the cutout size, not the outside size of the sink.
- Read the slab size off the tag, set your trim and gap, then compare the layout count with the area count.
Common questions about the numbers
- Why does it say 3 slabs when the area works out to 1.59?
- Area is a floor, not a plan. Take three 100 by 40 in pieces on a 126 by 63 in slab with a 1 in trim. Usable width is 61 in and two pieces side by side need 80 in, so no two can share a slab: the area allows 2 slabs, but the layout needs 3. The calculator shows both numbers so you can see the gap between them.
- Does this replace nesting software?
- No. It gives you a fast count before you quote. Nesting software works from real shapes, and some tools work from photos of the actual slab. Use it to size up a job before you spend time nesting it.
- Why do cutouts not reduce the slab count?
- This tool counts the whole rectangle, so the sink drop still takes room on the slab. A drop can sometimes be reused, and this tool does not plan for that. The drop shows up in finished area and yield.
- What is the gap between pieces?
- The width of stone the blade removes, plus any clearance you leave so two cuts do not touch. Every cut across a slab costs this width, so more pieces means more gap.
- Is the result a quote?
- No. A quote also needs your material price, edge and cutout rates, labor, install and tax. This page only handles the takeoff, so copy the summary or print it and use it in whatever you quote with.
Related reading
- Sink cutout templates: find the cutout size for a sink model.
- How to measure your countertops: a step-by-step measuring guide written for homeowners.
- Slab nesting guide: how nesting works and when it pays.
- Remnant slabs and how to price remnant jobs: what counts as a remnant and how shops price them.
- Vein matching: what it means and why it changes a layout.