Download
MeshOptimiser v0.37.3
One double-click installs it on Windows. Free, open source, MIT. Windows and macOS.
Get started
Double-click, wait, drop a file.
- 01
Double-click the installer
It downloads the app, adds MeshOptimiser to your Desktop and Start menu, and shows its progress as it goes. Run it again any time to update.
- 02
Let it set itself up
The first run sets itself up, then opens the viewer. After that it starts in about a second.
- 03
Drop a file
Drag in a STEP, GLB, FBX or OBJ file. STEP is converted first.
MeshOptimiser opens in its own window through Chrome, the browser its graphics are made for (Edge and Brave work too). No Chrome on your computer? The installer offers to get it for you, or download Chrome yourself.
On macOS, or to do it by hand: unzip the download anywhere and start it with one of these.
- Windows (by hand)
start.bat- macOS
./start.command- Command line
python step2glb.py input.step --meshopt
From 0.22.0 the app updates itself in Settings › Updates, and keeps the old version. Older versions need one manual update first. How updating works
Online or full app
Try it online. Download it for the rest.
The online version is the same app running in your browser, with nothing uploaded. It opens GLB, glTF, FBX, OBJ, 3MF and STL and has the same tools. The full app adds what a browser cannot do.
- CAD files
- STEP import, with parts, colours and CAD data.
- Claude
- The connection that lets Claude work with the open scene.
- Folders
- Open a folder, optimise many files in one go.
- Big models
- Large assemblies, without the browser running out of memory.
- Your computer
- Saved scenes, crash recovery, updates and offline use.
Versions
The last three releases.
Each is the exact code of that release, as a zip.
-
v0.37.3Latest27 Oct 2026
-
v0.37.226 Oct 2026
-
v0.37.125 Oct 2026
- Python
- 3.10, 3.11 or 3.12. Not 3.13 yet.
- Browser
- Chrome is best. Edge and Firefox work too. Safari on a Mac can lag.
- Disk
- About 2 GB for the first install.
- Network
- Not needed to run. A few rarely used converters download on demand.
Information
About this release.
- Status
- Before 1.0, so things may still change
- Platform
- Windows, macOS
- Requires
- Python 3.10 to 3.12, a browser with WebGPU, about 2 GB free for the first install
- Built with
- cadquery-ocp, trimesh, numpy, Draco, Assimp (WASM), WebGPU, plain JavaScript
- Licence
- MIT
- First published
- 5 May 2026
- Source
- github.com/xpayn3/MeshOptimiser