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About this tool
Convert between OBJ, STL and GLB, and see the mesh statistics for each.
The 3D Model Format Converter normalises a text OBJ mesh in the browser: it parses every v vertex line and every f face line, strips the texture and normal index groups so each face token keeps only its vertex index, and writes the result back out as a clean OBJ you can download. Alongside the file it reports the mesh statistics that matter before an import — total vertices, total faces, duplicate vertices matched to eight decimal places, and degenerate faces with fewer than three distinct indices. The file never leaves your machine; parsing and rebuilding happen in the page.
Open 3D Model Format Converter on AltFTool — it loads instantly in your browser.
Choose an ASCII OBJ mesh under Local file(s); only the first selection is used, and the mesh is read in the page rather than uploaded.
Press Run local workbench to parse every v vertex and f face line and strip the v/vt/vn index groups down to bare vertex indices.
The rebuilt mesh downloads as altftool-normalized.obj, and the Verified result panel reports vertices, faces, duplicate vertices and degenerate faces.
Faces written as v/vt/vn are rewritten to bare vertex indices, which is the form the strictest OBJ readers accept.
The same pass reports vertex and face totals, duplicate vertices and degenerate faces, so you see what you are converting.
The rebuilt file is plain ASCII OBJ — all vertices, then all faces — so you can diff it or hand-edit it afterwards.
Text OBJ in, text OBJ out. It matches lines starting with v and f, so a binary STL, glTF, GLB or FBX will parse to zero vertices and report that no OBJ geometry was found. Export to ASCII OBJ from your modelling tool first.
No. The normalised output keeps vertex positions and face connectivity only — UV coordinates, vertex normals, smoothing groups, object and group names and the .mtl material reference are all dropped. Keep the original file if you need any of those; this output is for geometry.
It is the number of vertex lines whose x, y and z values match another line once rounded to eight decimal places. A high count usually means the exporter split vertices per face rather than welding shared corners, which is expected for render-ready meshes but worth merging before sculpting or printing.
No. The file is read with the browser's own file reader, parsed in the page, and the rebuilt OBJ is created as a local blob download. Nothing is transmitted, which is the point if the asset is client work or unreleased.
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