Drop an STL file and download an equivalent Wavefront OBJ, converted entirely in your browser.
The file is opened locally in your browser and is never uploaded.
The converter parses binary and ASCII STL files, welds identical vertex positions into a shared vertex list, computes one face normal per triangle, and writes a Wavefront OBJ with v, vn and f records. Welding means the OBJ is usually smaller and easier to edit than a raw per-triangle dump, and each face references its normal with the v//vn form. STL stores no colour, material, texture or unit information, so none can appear in the OBJ, the conversion is geometry-only. Very large meshes produce large text files and are limited by browser memory.
Will the OBJ look the same as the STL? Yes, the triangle geometry is identical. The OBJ welds duplicate vertices and adds computed face normals, but it does not smooth, repair or simplify the mesh.
Does the converter keep colours or materials? No. STL has no colour or material data to keep, so the OBJ contains geometry and normals only, with no MTL file.
Is my file uploaded for conversion? No. The STL is parsed and the OBJ is generated in your browser tab; the download is created locally.