Convert Rhino 5 to Rhino 4 (Free)
Also converts STL, OBJ, GLB, PLY, USDZ, 3MF from the same file.
Runs in your browser. No upload, no signup, nothing to install.
Also from Innerscene: Circadian Lab, a free lighting calculator for room illuminance, melanopic EML, and glare.
Why save as Rhino 4
Rhino opens files saved by older versions, never files saved by newer ones. A file in Rhino 5 format, which Rhino 5 saves, is refused by every earlier release, so a colleague, a client or a machine still on an older version cannot open it. A copy saved as Rhino 4 opens in Rhino 4 and later.
How to convert Rhino 5 to Rhino 4
- 1
Open your .3dm file
Drag it onto the viewer above, or click "Open a Rhino File". It is read in your browser.
- 2
Choose Rhino 4 in the Export menu
Click Export in the toolbar. In the Rhino (.3dm) row, click 4.
- 3
Save the Rhino 4 file
The file is written in your browser and saved straight to your downloads folder.
What survives the conversion
The viewer hands your original file to openNURBS, the library Rhino itself uses to read and write .3dm files, and saves it again as Rhino 4. Nothing is remeshed or rebuilt.
| Rhino objects | Kept | NURBS surfaces and polysurfaces, curves, meshes, point clouds, text, dimensions and lights are copied as themselves. Nothing is turned into a mesh along the way. |
|---|---|---|
| Extrusions | Reduced | Lightweight extrusion objects arrived in Rhino 5. In a Rhino 4 file each one becomes the polysurface with the same shape. |
| Layers and settings | Kept | Layers with their names, colors and nesting, materials, the unit system and the model tolerances carry across. |
Layers you switch off in the Layers panel are left out of the saved file. If you change the model with the Edit menu (scale, rotate, mirror) first, the export is written from the edited display meshes instead, so every object arrives as a mesh.
Rhino versions
Each Rhino version and the Rhino releases that save it. A release opens its own version and every older one.
| Version | Year | Saved by | In the file | This viewer |
|---|---|---|---|---|
| Rhino 8 | 2023 | Rhino 8 | archive 80 | Opens and saves |
| Rhino 7 | 2020 | Rhino 7 | archive 70 | Opens and saves |
| Rhino 6 | 2018 | Rhino 6 | archive 60 | Opens and saves |
| Rhino 5 | 2012 | Rhino 5 | archive 50 | Opens and saves |
| Rhino 4 | 2007 | Rhino 4 | archive 4 | Opens and saves |
| Rhino 3 | 2003 | Rhino 3 | archive 3 | Opens |
Your file never leaves your computer
Both the Rhino 5 parser and the Rhino 4 writer are JavaScript and WebAssembly running in your own browser tab. There is no upload step, no server-side conversion queue, and no copy of your file anywhere but your machine. That matters for drawings under NDA, for client work, and for anything you would not email to a stranger.
Free to Use, No Signup
There are no accounts and no watermarks on this converter. If it saved you time, the one thing we ask is a mention: a post, a link from your blog or course page, or a reply to someone asking how to open a file.
Share it
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Hear about new formats
Occasional emails when the viewer learns a new format or gets a new tool.
Frequently asked questions
▶Is this Rhino 5 to Rhino 4 converter free?
Yes. No signup, no watermark, no per-file limit and no paid tier. Innerscene.
▶Is my Rhino 5 file uploaded anywhere?
No. The file is read with the browser file API and converted in the same tab. Nothing is sent to a server unless you explicitly click Share, which is a separate, opt-in feature.
▶Which versions of Rhino open the Rhino 4 file?
Rhino 4 and later. The file is a standard Rhino 4 file (archive 4), the version Rhino 4 saves.
▶What changes when the file is saved as Rhino 4?
Lightweight extrusion objects arrived in Rhino 5. In a Rhino 4 file each one becomes the polysurface with the same shape.
▶Can I convert Rhino 4 back to Rhino 5?
There is no need: Rhino 5 opens Rhino 4 files directly. Anything listed above as reduced stays reduced, so keep your original Rhino 5 file as the master copy.
▶Which browsers does it work in?
Chrome, Edge, Firefox and Safari, on Windows, macOS, Linux, iOS and Android. No plugin and no extension.
Other Rhino version conversions
Convert Rhino to another format
Or start from the universal 3D viewer.