Reference · updated 20 October 2026
3D formats store different things. Convert with that in mind.
Most “the file did not survive” complaints are format mismatches: the target cannot hold what the source
contained. This page lists what each format carries, in the order people meet them.
What each format carries | Format | Carries | Drops | Typical use |
|---|
| STL | Triangles, optional normals | Colour, materials, units, names, animation | 3D printing; the lowest common denominator |
| OBJ | Vertices, faces, texture coordinates, normals, .mtl references | Animation, rigging, scene hierarchy in practice | Exchanging static meshes between DCC tools |
| PLY | Arbitrary vertex properties: position, colour, normals, confidence | Faces in some point-cloud exports; materials | Scans, photogrammetry, point clouds |
| GLB / glTF | Mesh, PBR materials, textures, animation, scene graph | Almost nothing; the most complete open format here | Web viewers, real-time apps, game engines |
| FBX | Mesh, materials, rigs, animation, cameras, lights | Portability: versions and exporters differ widely | Animation and game pipelines |
| 3MF | Mesh, units, parts, colour, print settings | Animation; some slicers ignore advanced extensions | Modern 3D printing exchange |
| DAE | Mesh, materials, animation, scene graph (XML) | Popularity; tool support is uneven today | Legacy interchange, some CAD handoffs |
| STEP | Exact CAD geometry (B-rep), units, tolerances | Tessellation state, materials as mesh tools understand them | Engineering exchange; not a mesh format |
Mesh vs CAD STL, OBJ, PLY, GLB, FBX, 3MF and DAE describe surfaces as triangles. STEP describes exact geometry as boundaries and curves. Converting STEP to a mesh is a tessellation decision, not a file-format switch: the result depends on the tolerance you choose.
Picking a target format
- For a printer. STL when the slicer only accepts STL, 3MF when units and parts must survive. Check the mesh is watertight either way.
- For a browser viewer. GLB: one file, packed buffers, materials included.
- Between modelling tools. OBJ travels well for static meshes. For rigs or animation, stay in FBX or glTF and verify the rig survived.
- From a scan. PLY keeps per-vertex colour and confidence that STL would throw away. Decimate before exporting to a printable format.
Verification checklist after converting
- Triangle count. Compare before and after. A large unexplained drop means geometry was not read.
- Bounding box. Compare dimensions with the source; a silent unit change shows up here first.
- Normals. Look for black patches or inverted faces in the target viewer.
- Manifold check. Non-manifold edges print badly; most slicers flag them.
- File size sanity. Binary STL is 50 bytes per triangle plus an 84-byte header — a quick integrity check.
Guides on this site
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