For 3D printing enthusiasts, makers, and CNC machinists, G-Code and the latest binary BG-Code are essential daily formats. Each time you slice a model in software like Bambu Studio, PrusaSlicer, OrcaSlicer, or Cura, you export one or more G-Code files to print or machine.
However, when organizing or checking these files in folders, macOS presents a frustrating bottleneck: Finder cannot natively display G-Code/BG-Code files, leaving you with a sea of generic, identical blank document icons.
To verify which 3D model a G-Code file corresponds to, you traditionally have to wait for a full slicer application to load. That extra launch step slows down routine file checks.
The New Solution: 3D Toolpaths Independently Rendered by GCodePreview
Designed specifically for macOS, GCodePreview integrates seamlessly into the native Quick Look and Thumbnail extension APIs of Finder. It provides a massive efficiency upgrade over traditional workflows:
- Automatic Finder Thumbnails: G-Code/BG-Code file icons in your folders are automatically replaced with detailed 3D toolpath visualizations. No more guessing.
- Instant Quick Look (Spacebar): Select a file and hit Spacebar to instantly view high-resolution 3D toolpaths in Finder, responding within milliseconds.
- 100% Local Parsing (Independent of Embedded Images):
Many basic preview extensions can only extract embedded PNG thumbnails (Base64) saved by slicers. If you disable thumbnail output in your slicer settings, or use legacy slicers that don't support it, those extensions fail to show anything.
GCodePreview features a built-in high-performance G-Code path parser. It reads nozzle movements such as G0 and G1 and reconstructs 3D toolpaths locally on your Mac. It can therefore generate a preview even when the file has no embedded thumbnail.
If thumbnails do not refresh immediately after installation, it is usually due to macOS system cache lag. You can refer to our Troubleshooting Guide to resolve it in seconds.
Comparison of G-Code Preview Methods
Here is a head-to-head comparison of GCodePreview against traditional viewing workflows to highlight the efficiency gains:
| Preview Method | Finder Thumbnails | Startup Time | No-Thumbnail Support | Data Privacy (Offline) |
|---|---|---|---|---|
| GCodePreview | Supported (Auto-generated) | < 1 second (Native) | Supported (Parses paths) | 100% Local |
| Traditional Slicers (e.g., Bambu Studio) | Not Supported | Requires full application launch | Supported (Fully loads file) | 100% Local |
| Online 3D Viewers | Not Supported | Depends on upload speed | Supported (Requires upload) | Low (Upload privacy risks) |
Bring native G-Code and binary BG-Code thumbnails and Quick Look previews to macOS Finder. Auto-parse paths, view files instantly.