Free STL (.stl) to PLY (.ply) converter — running entirely in your browser. No upload, no signup, no file limits: your files never leave your device.
STEP · IGES · BREP · STL · OBJ · PLY · GLB · glTF · 3MF · COLLADA · AMF · FBX · 3DS · OFF · LAS · PCD · XYZ · PTS
STL is the de-facto standard for 3D printing. It describes a model purely as a mesh of triangles — no color, no units, no assembly structure — which makes it simple, universally supported, and the required input for virtually every slicer, from PrusaSlicer and Cura to resin-printer tools.
PLY was designed at Stanford for storing 3D-scanned data. Beyond plain geometry it can attach arbitrary per-vertex properties — most importantly vertex colors — which makes it the format of choice for 3D scans, photogrammetry output and point-cloud-derived meshes.
| STL | PLY | |
|---|---|---|
| Geometry | Triangle mesh | Triangle mesh / scan data |
| Units | No — unitless numbers | No |
| Colors & materials | No | Per-vertex colors |
| Animations | No | No |
| Typical use | 3D printing | 3D scans & photogrammetry |
Yes — free with no accounts, no watermarks and no file-size limits. Conversion runs on your own machine, so there are no server costs behind it.
No. The converter runs entirely in your browser using WebAssembly. Your .stl file never leaves your device, which makes it safe for confidential designs.
Yes — parts and assembly hierarchy are preserved where PLY supports them, and you can optionally merge everything into a single mesh during conversion.
Yes. Every converted model opens in the built-in 3D viewer with an assembly tree, display modes and section views, so you can inspect the result first.
STL already contains only unitless triangles, with no part names, colors or design history for a converter to preserve. The PLY result has no declared units and does not carry textures, animation or an assembly tree.