Format conversion/Mesh ↔ mesh
OBJ to STL converter (local)
Convert OBJ to binary STL without sending the file anywhere. OBJ text is read in 4 MiB slices, polygon faces are fan-triangulated in the Worker, and the binary STL is assembled as a local download.
Conversion
No uploadReady to convert
The input is streamed in 4 MiB slices; the output is assembled in the Worker and downloaded locally.
- Formats
- OBJ → STL
- Worker
- in your browser
Drop an OBJ here
OBJ text streams in 4 MiB slices. Quads and polygons are fan-triangulated; groups merge into one mesh.
Choose a fileMax file size: 500 MB · No upload
No upload · File.slice() → Worker → chunked STL output.
How it works
- 1
Drop an OBJ file.
- 2
The Worker streams v and f records, resolves positive or negative vertex indices, and fan-triangulates quads and polygons.
- 3
Groups are merged into one triangle mesh; the binary STL writer computes a face normal for every triangle.
- 4
Download the binary STL generated locally.
What the numbers mean
OBJ is unitless. Coordinates are written to STL without rescaling; confirm the intended scale before printing.
STL stores one face normal per triangle. The writer computes a normalized normal and falls back to zero for degenerate faces.
Printing notes
- Binary STL is smaller and faster to load than ASCII STL.
- OBJ groups and objects are merged into one mesh; separate parts must be split before conversion if the slicer needs distinct objects.
- Check the converted bounds against the printer bed.
Questions
References
- · Wavefront OBJ specification
- · Binary STL format