Convert OBJ to PLY
Convert OBJ to PLY in your browser. The conversion runs on this page and the file never leaves your computer.
Result
Before you convert: what this keeps and what it destroys
Preserved
- The geometry, triangle for triangle
- Overall dimensions and proportions
- Watertightness, where the input is watertight
- Colour
Destroyed
- A recorded unit: PLY stores none
- The separation between parts, merged into one body
↺ the reverse: PLY → OBJ · about .obj · about .ply · just view it instead
Why people convert OBJ to PLY
A mesh going into MeshLab, CloudCompare or a research pipeline, which is what PLY is for.
There is an irony worth naming here. PLY's best feature is per-vertex colour stored in the file, and OBJ keeps its colour in a separate .mtl that a single-file upload never includes, so the one thing this target does better than most is the one thing the source cannot supply. What you get is clean triangulated geometry ready to be measured or decimated.
Faces with more than three sides, which are common in OBJ, are triangulated on import. Neither format carries a unit, so the numbers pass through untouched.
What you get
You get a binary PLY file containing the same triangles the OBJ file described. No geometry is added, removed or approximated: mesh-to-mesh conversion is a change of container, and this site's tests check that the triangle count comes out identical.
Carried across: colour available in the selected OBJ (external materials are not read).
Not carried across by this conversion: a recorded unit, the assembly structure.
The conversion runs in your browser. Your file stays on your computer and is not uploaded.
What to check afterwards
- OBJ carries no unit. The numbers in the file are just numbers, so the conversion assumes millimetres. Check the overall dimensions of the result before you commit to machining or printing it. A file exported from a package set to inches will be 25.4 times out.
- Separate parts merge into one body. OBJ can describe an assembly and PLY cannot, so a multi-part model arrives as a single mesh. 3MF and GLB both keep the structure if you need it.
- Coordinates are stored as 32-bit floats. For a part measured in millimetres that's far finer than any machine tolerance. For a model spanning hundreds of thousands of units it isn't.
If you need something this conversion cannot give you
If the unit has to be unambiguous, convert to 3MF instead. It records the unit in the file, so nobody downstream has to assume millimetres and nobody has to scale by 25.4 after the fact.
If the parts must stay separate, convert to 3MF or GLB. Both keep a real structure, so a five-part assembly arrives as five parts rather than one merged body.
Going the other way
Convert PLY back to OBJ. The reverse conversion also works with mesh geometry. It does not reconstruct exact CAD surfaces. Material data and part structure lost in either direction cannot be restored by converting back. Keep the original file for later edits.
How we know this conversion works
This pair was checked against 3 files from the test corpus on 2026-09-04. Each run parses its own output back in and compares the bounding box, the triangle count and, for closed solids, the volume against the input.
A pair that fails those checks doesn't get a page. That's why this site lists 120 conversions and not the several hundred a format-times-format grid would suggest.