A small workshop we know cuts parts out of aluminium sheet. Before every job someone has to decide where each part goes on the sheet — the "nesting" — and that decision is most of the waste. Good nesting software exists, but it is priced for factories. So we wrote one for them, and today we are giving it to everyone: Nestio is free, open source, and runs entirely in your browser.
What it does
- Reads your drawing as it is. Drop a DXF or DWG. Lines, arcs, circles, splines, polylines and blocks become closed outlines; outlines inside outlines become holes. Parts drawn as 3D wireframes are flattened automatically, and anything that looks wrong — an odd thickness, a face that could not be resolved — is flagged for you to check.
- Finds your sheets. Rectangles on a sheet layer, or clearly bigger than every part, are taken as sheets. You can change sizes and counts, add more, and mix several sheet sizes in one job.
- Uses the holes. Small parts that fit inside the cut-outs of bigger ones are placed there first, keeping the spacing you asked for.
- Uses as few sheets as possible. Parts are rotated freely (never mirrored) and packed sheet by sheet. At the end Nestio tries to empty the last sheet into the earlier ones and compresses what is left, so the spare material stays at one end as a single piece you can use later.
- Checks its own work. Every result goes through an independent check: is each part inside the margin, is every gap at least the spacing you set. Then you download a DXF with the sheets, the cut contours, the labels and the remnant on separate layers.
On the sample drawing in the repository — 46 parts, including flanges and frames with large cut-outs — Nestio fits everything on one 3000 × 1500 mm sheet in under a minute on a laptop, 18 of them inside other parts' holes.
Your drawing never leaves your computer
There is no upload. The page loads its own code once; after that all the work happens in your browser, on your own processor, spread over all of its cores. There is no account, no cookie and no tracking code. Close the tab and nothing remains anywhere but on your machine.
Built on open research
The packing itself is sparrow, a state-of-the-art nesting heuristic published by Jeroen Gardeyn and colleagues at KU Leuven, built on their collision engine jagua-rs. DWG files are read with LibreDWG. We added everything around them — reading real drawings, flattening 3D parts, filling holes, working sheet by sheet, the checks and the interface — and compiled it all to WebAssembly so it runs without installing anything.
Free, and staying free
No payment, no sign-up, no limits. The source code is on GitHub under the GPL-3.0 licence: read it, run it on your own machine, improve it. If a drawing does not come out the way you expect, open an issue — that is how the tool gets better.
