Sheet Nesting Calculator
Work out how many rectangular blanks fit on a sheet, how many sheets a run needs, and how much of each sheet ends up as scrap. Enter the blank size, the spacing your cutting process needs and the edge margin; the calculator tries the blank as drawn, rotated, and in mixed bands of both, and draws the best layout.
Blanks per sheet
Enter the blank width and height. The sheet defaults to 48 x 96 in; pick another size above.
How the layout is found
- Usable sheet: width and length less the edge margin on both sides.
- Blanks along one side: n = floor((usable length + spacing) / (blank + spacing)), because n blanks take n x blank + (n - 1) x spacing.
- Layouts compared: a grid as drawn, a grid rotated 90 degrees, rows as drawn with the rest of the length in rotated rows, and the same split across the width. Every split point is tried and the highest count wins.
- Utilization = blanks x blank area / gross sheet area. Scrap is everything else, margins and webs included.
The result is a rectangle estimate. It does not account for lead-ins, microjoints, part-in-part nesting or remnant reuse, and a shop's nesting software will usually beat it on irregular parts. Stock sizes are listed on the standard sheet sizes chart.
Blanks per 48 x 96 in sheet
Computed with the calculator above, rotation allowed. The second column adds a 0.125 in web between blanks and a 0.25 in edge margin, typical of a laser nest; note how 12 in blanks lose a row and column, and how trimming them to 11.75 in wins them back.
| Blank (in) | No kerf, no margin | 0.125 in spacing, 0.25 in margin |
|---|---|---|
| 6 x 6 | 128 (100.0%) | 105 (82.0%) |
| 8 x 8 | 72 (100.0%) | 55 (76.4%) |
| 10 x 10 | 36 (78.1%) | 36 (78.1%) |
| 12 x 12 | 32 (100.0%) | 21 (65.6%) |
| 11.75 x 11.75 | 32 (95.9%) | 32 (95.9%) |
| 12 x 24 | 16 (100.0%) | 10 (62.5%) |
| 16 x 16 | 18 (100.0%) | 10 (55.6%) |
| 18 x 18 | 10 (70.3%) | 10 (70.3%) |
| 24 x 24 | 8 (100.0%) | 3 (37.5%) |
| 20 x 30 | 6 (78.1%) | 6 (78.1%) |
Count per sheet, with utilization of the gross sheet area in brackets.
Need the blanks cut and formed? Send a DXF, drawing or STEP file and U.S. shops quote it, or browse sheet metal fabricators.
Frequently asked questions
- How many blanks can I cut from a 4 x 8 sheet?
- Divide each sheet dimension, less the edge margins, by the blank size plus the spacing, round down, and multiply. With no kerf or margin, 12 x 12 in blanks fit 4 x 8 = 32 on a 48 x 96 in sheet. Add a 0.125 in web between parts and a 0.25 in edge margin and only 3 fit across and 7 along, so the count drops to 21. Nominal-size blanks on a nominal-size sheet always lose a row once kerf is counted.
- What spacing should I leave between laser cut parts?
- Enough for the kerf plus a web that keeps the skeleton rigid and stops heat from one cut affecting the next. On a laser that is often around the sheet thickness, with a floor of a couple of millimeters on thin gauge; plasma needs more. Blanks sheared on a common line need none. Your shop’s nesting settings are the real answer.
- Should I allow the blanks to rotate?
- Usually yes, it often gains parts. Turn it off when direction matters: parts that are bent should have their bend lines across the rolling direction where possible, and brushed, polished or embossed sheet has a visible grain that has to match on the finished part.
- How is material utilization calculated?
- Utilization is the area of the blanks divided by the gross area of the sheet. For a run, the job figure divides the area of every blank by the area of every sheet used, so a nearly empty last sheet pulls it down. Scrap is the rest, including the edge margins and the web between parts.
- Will nesting software do better than this?
- For irregular parts, yes. This calculator works on the rectangle around each blank and tries grids and two-band mixed layouts. True-shape nesting interlocks irregular parts, fits small parts inside the cutouts of large ones and uses common-line cutting, all of which raise utilization. Treat the result here as a planning estimate for material and sheet count.
