# PLY to STL Converter

> Print 3D scans and photogrammetry: PLY to STL in your browser, with a fix for scans saved in metres and a check for holes before you slice.

Page: https://printpal.io/convert/ply-to-stl
Updated: 2026-11-12
Use it: open https://printpal.io/convert/ply-to-stl in a browser and drop a file. Free, no account, files are processed locally and never uploaded.

Scanners and photogrammetry apps write PLY meshes with vertex colors. STL keeps the triangles and drops the colors. PLY has no units; the numbers pass through as millimetres, so a scan saved in metres comes out tiny, and the converter offers to read it as metres instead.

Raw scans are rarely watertight: there is usually a hole where the object stood. Check the STL in the [STL viewer](https://printpal.io/tools/stl-viewer), then close the holes in [Mesh Repair](https://printpal.io/tools/mesh-repair). Point-cloud PLYs have no surface and must be meshed first.

## How to convert PLY to STL

1. **Drop your PLY files.** Drop .ply meshes or point clouds, ASCII or binary.
2. **Check the preview.** The model appears at the size and orientation it will have. Fix the file units, up axis or size under Size, units and orientation if needed.
3. **Choose STL options.** Binary STL by default (smallest, read everywhere). Tick ASCII only if an old tool asks for text STL.
4. **Convert and download.** One file downloads straight away. A batch gives a download per file and one .zip of all of them.

## What carries over

| | Result |
|---|---|
| Geometry | Every face is kept; quads and n-gons are split into triangles. |
| Color | Dropped: STL cannot store color. |
| Units | PLY has bare numbers, so they pass through as millimetres: 1 unit becomes 1 millimetre. If the preview size is wrong, set the file units. |
| Orientation | Turned from Y up to Z up, so it stands on the plate in a slicer. |
| Objects | Merged into one surface: STL has no objects. |

## PLY at a glance (Polygon File Format (Stanford Triangle Format))

Greg Turk designed PLY at Stanford in the 1990s for 3D scan data, and it is still what scanners, photogrammetry tools and MeshLab write. It can hold a colored mesh or a bare point cloud, and Gaussian splat captures reuse it for splats.

- **Stores:** Vertices with any properties, optional faces; ASCII or binary
- **Color:** Per-vertex colors
- **Units:** None; scanners usually write metres
- **Up axis:** Varies with the scanner or app
- **File size:** Binary is compact; ASCII is several times larger
- **Opens in:** MeshLab, CloudCompare, Blender, scanning and photogrammetry software

## STL at a glance (Stereolithography (Standard Triangle Language))

Created by 3D Systems in 1987 for the first stereolithography printers, STL is still the format every slicer and print service accepts. It describes a surface as a list of independent triangles, with no shared vertices, units, colors or scene structure.

- **Stores:** Loose triangles: three corners and a normal each, binary or ASCII
- **Color:** None in the standard
- **Units:** None written; slicers assume millimetres
- **Up axis:** Z, the slicer convention
- **File size:** 50 bytes per triangle in binary, about 5 times that as ASCII
- **Opens in:** Every slicer, CAD tool and 3D app

## Tips

- **Point cloud?** Mesh it with Poisson reconstruction in MeshLab or CloudCompare first.
- **Heavy scans** Millions of triangles slow slicers down. Decimate in MeshLab or Blender before printing.
- **Keep the color** Use [PLY to OBJ](https://printpal.io/convert/ply-to-obj) to keep vertex colors.

## FAQ

### Why is my STL from PLY so small?

PLY has no units and many scanners write metres. Set the file units to metres (the converter suggests it when the size looks wrong).

### Can I convert a PLY point cloud to STL?

Not directly: a point cloud has no surface. Reconstruct a mesh first, then convert it.

### Are vertex colors kept?

Not in STL, which has no color. OBJ, GLB and PLY keep them.

### Is the converter free? Are there limits?

Free, with no sign-up, watermark or file count limit. Batches and files of a few hundred MB work on most laptops; the only limit is your device's memory.

### Are my files uploaded?

No. Files are read and written by JavaScript and WebAssembly in your browser and never sent to PrintPal. The STEP and IGES reader is the only extra download, once, from a public CDN.

## Related

- [STL to OBJ Converter](https://printpal.io/convert/stl-to-obj)
- [STL to 3MF Converter](https://printpal.io/convert/stl-to-3mf)
- [STL to GLB Converter](https://printpal.io/convert/stl-to-glb)
- [STL to PLY Converter](https://printpal.io/convert/stl-to-ply)
- [PLY to OBJ Converter](https://printpal.io/convert/ply-to-obj)
- [STL to USDZ Converter](https://printpal.io/convert/stl-to-usdz)
- [OBJ to STL Converter](https://printpal.io/convert/obj-to-stl)
- [3MF to STL Converter](https://printpal.io/convert/3mf-to-stl)
- [3D model viewer](https://printpal.io/tools/3d-model-viewer)
- [3D model converter](https://printpal.io/tools/3d-model-converter)
- [Mesh Repair](https://printpal.io/tools/mesh-repair)
- PrintPal for LLMs: https://printpal.io/llms.txt