An STL that says its own size.
Turn an STL into a 3MF in your browser, nothing uploaded: millimetres written in the file so no slicer has to guess, checked before you download it.
By Suraj Kumar3 min read
An STL never says whether its numbers are millimetres or inches; a 3MF does. KeepSimp writes a 3MF from an STL in your browser, with the unit in the file.
Drop the STL and download the 3MF.
Open STL to 3MF and drop the .stl on it. Check its size: the STL is read in millimetres, and you can choose inches or another unit if it was made in one. Press Download 3MF.
Before the file is offered, KeepSimp opens it again with its own reader and counts its triangles and measures its size; a file that does not match the model is not offered, and the page says what was wrong.
What the 3MF holds.
The shape in millimetres, with the unit named in the file; corners at the same place joined into one, and triangles with no area left out, as the 3MF specification asks.
A shape that is not closed is marked as a surface rather than a solid, and the page says so: a slicer may not print it.
Checked by the 3MF Consortium's own reader.
KeepSimp's 3MF files are held in its tests to lib3mf, the 3MF Consortium's library, in its strict mode, with every part closed and turned outwards.
Further reading
Topics: stl to 3mf · convert stl to 3mf · stl to 3mf converter · stl to 3mf online · why use 3mf
A little less theory. A little more doing.
Try it on your own terms, with a free browser tool.
Try the tool