Convert 3DM to PLY
Convert 3DM 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 shape, to within the tessellation tolerance
- Overall dimensions and proportions
- Watertightness, where the input is watertight
- Colour
Destroyed
- Exact curves and surfaces, replaced by triangles
- The feature tree and any parametric history
- A recorded unit: PLY stores none
- The separation between parts, merged into one body
Why people convert 3DM to PLY
The analysis route out of Rhino. PLY is what MeshLab and CloudCompare expect, and it is the format to pick when the model is going to be measured, decimated or compared against a scan rather than rendered or printed.
PLY carries colour per vertex with no sidecar, so Rhino's object and layer colours come through and a multi-part model stays legible as a mesh.
The unit comes from the 3DM's own declaration, so the geometry is correctly sized. As with every route out of Rhino, what is converted is the saved render mesh, and anything without a surface is reported as skipped rather than silently dropped.
What you get
You get a binary PLY file containing triangles. The reader tessellates supported surfaces or uses saved render meshes where required by the source format. Inspect curved faces at the intended output size. The triangle count depends on the model and the reader's meshing settings.
Carried across: supported base or vertex colour.
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
- 3DM declares its unit in the file. Check the output dimensions in the receiving application, especially when its import settings can override the unit.
- Separate parts merge into one body. 3DM 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.
- Curves become facets. 3DM stores exact surfaces, so a hole is a cylinder with a radius. PLY stores triangles, so that cylinder becomes a many-sided prism. Look at curved faces in the result at the size you intend to make the part.
- 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.
If you need editable CAD geometry, don't convert at all. Open the 3DM file directly in FreeCAD, Fusion, Onshape or SolidWorks. Every mesh format destroys the exact surfaces, and no later conversion brings them back.
Going the other way
This site reads 3DM but does not write it. For the reverse conversion, use an application that can export 3DM.
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.