How to convert PLY to STL
- Drop your .ply file into the box above, or click Choose file.
- Check the 3D preview, size and triangle count.
- Make sure STL is selected as the output format. Adjust scale or up-axis if needed.
- Click Download. The .stl file is created instantly on your device.
Why convert PLY to STL?
PLY is what 3D scanners and many dental intraoral scanners export. Converting PLY to STL lets you print the scan or send it to a lab or CAD program that only takes STL. Per-vertex colour is dropped; geometry stays the same.
What changes in the conversion
- Colours are dropped. STL only stores geometry.
- Units. STL is defined in metres. Large models (in millimetres) are scaled ×0.001 automatically so they appear at real size.
- Geometry is preserved. Every triangle, with all object transforms applied, ends up in the new file.
PLY vs STL
| PLY | STL | |
|---|---|---|
| Full name | Polygon File Format | Stereolithography |
| Stores | geometry, per-vertex colours and normals | geometry only |
| Colour | Yes | No |
| Textures | No | No |
| Units | none | none – most programs read STL numbers as millimetres |
| Exact CAD geometry | No | No |
About the formats
PLY (Polygon File Format) was created at Stanford University in the 1990s for 3D scanning research. It stores polygons or point clouds with optional per-vertex colour and normals, in ASCII or binary form. It is the common output of 3D scanners, photogrammetry and dental intraoral scanners.
STL (Stereolithography) was created by 3D Systems in 1987 for its stereolithography printers. It describes only the surface of a model as a list of triangles, without colour, materials or units. It is the default file for 3D printing and the format almost every slicer (Cura, PrusaSlicer, Bambu Studio, Chitubox) opens.
Frequently asked questions
Is this converter free?
Yes. You can convert PLY to STL for free – up to 3 conversions a day, with no sign-up and no watermark. If you need more, Pro gives you unlimited conversions and batch conversion (free for 7 days).
Are my files uploaded to a server?
No. The conversion runs entirely in your browser using WebAssembly and JavaScript. Your model never leaves your computer, which also makes it safe for confidential parts and patient data.
Is there a file size limit?
There is no fixed limit. Files of a few hundred megabytes work on a typical laptop; the practical limit is your device's memory.
My PLY is a point cloud – can it be converted?
A point cloud has points but no surface. STL needs triangles, so a point cloud must be meshed first (e.g. Poisson reconstruction in MeshLab or CloudCompare). The viewer will show the points, but STL export will be empty.