Convert PLY to OFF
Free PLY to OFF converter that runs in your browser. See real dimensions before you download.
How to convert PLY to OFF
- Drop your PLY file onto the converter — it opens in your browser, nothing is uploaded.
- Check the preview and the dimensions in mm; fix units or the up axis in “Units & orientation” if the size or orientation looks wrong.
- Choose OFF as the output and click Convert. Several files download as one ZIP.
What carries over from PLY to OFF
| PLY | OFF | Result | |
|---|---|---|---|
| Colour / materials | Yes | No | Dropped |
| Textures | No | No | — |
| Units stored in file | No | No | Numbers in mm |
| Separate parts | No | No | — |
| Usual up axis | Z | Z | Unchanged |
About PLY files
PLY was developed in the mid-1990s by Greg Turk and colleagues at the Stanford Graphics Lab to store data from 3D scanners, and the Stanford Bunny and Happy Buddha models made it famous. A PLY file starts with a text header that declares elements, such as vertex and face, and the properties each element has. The body then follows in ASCII, binary little-endian or binary big-endian. Because properties are declared in the header, a file can carry any extra per-vertex data: normals, colour channels, intensity, confidence or custom scalars. This flexibility made PLY a standard output for scanners, depth cameras, photogrammetry and point-cloud tools. It can store a point cloud with no faces at all, or a polygon mesh. It does not define units or a scene structure.
About OFF files
OFF, the Object File Format, was defined for Geomview, an interactive geometry viewer developed at the Geometry Center at the University of Minnesota in the 1990s. A file is plain text. The first line holds the keyword OFF, the second gives the counts of vertices, faces and edges, then each vertex appears as three coordinates and each face as a vertex count followed by index numbers. Variants add colour (COFF), normals (NOFF) or texture coordinates (STOFF) through prefixes, and colour is optional at the end of each line. The simplicity made it a favourite in computational geometry, and benchmark sets such as ModelNet used it for machine-learning research on shape classification. CGAL and libigl read and write it directly. It has no units, materials or scene structure, so it is rarely a printing format, but converting it is common.
3D printing notes
PLY is the format many handheld scanners and photogrammetry tools produce, and several slicers can import it as a mesh. A scanned PLY almost always needs work before it prints: noise, holes at the scan boundaries and an open base. Scans are often in metres or in arbitrary scanner units, so check the dimensions before slicing. A PLY that only has points and no faces cannot be turned into a printable solid without surface reconstruction in a tool such as MeshLab. MeshShift reads and writes PLY, shows size and watertight status, and its print check can fill holes and rebuild a closed manifold solid at the same size, ready to save as STL or 3MF.
Frequently asked questions
Is this PLY to OFF converter free and private?
Yes. The conversion runs in your browser with JavaScript and WebAssembly, so your PLY file is never uploaded to a server. There is no sign-up, no watermark and no daily limit; very large files are limited only by your device's memory.
Does PLY store colour?
Yes, usually as red, green and blue values attached to each vertex, not as a texture image. Colours are smooth across triangles, which suits scans. Many slicers ignore vertex colour, so use 3MF or another format if you need to preserve it for printing.
What is an OFF file used for?
OFF is a simple mesh format used mainly in geometry processing and machine-learning research. Datasets like ModelNet ship as OFF because the format is easy to parse. It is a plain text list of vertices and faces.