Free online STL viewer
View STL files online, locally by default.
Caddis provides a simple browser-based STL viewer for quick 3D model inspection. Open a model directly from your device, then use the same workspace you use for CAD drawing review.
No account required for local viewing. Files stay on your device unless you opt into Cloud.What is an STL file?
STL is a widely used mesh format for 3D printing and model exchange. It describes a surface as a collection of triangles rather than editable CAD features.
Measure a stair run on siteField-review workflow
From drawing to clear feedback.
- 01Open the Caddis web viewer.
- 02Select an STL file from your device.
- 03Inspect the model locally in your browser.
Built for practical review
Your drawings stay under your control
Caddis is local-first: opening a supported file for local review does not require uploading it. If you choose Caddis Cloud, you can continue a project across devices or create a revocable, read-only link.
Frequently asked questions
Do I need an account to use Caddis?
No. You can open and review supported files locally without creating an account. An account is only needed for optional cloud features.
Are my CAD files uploaded?
Not for local viewing. Caddis processes supported files on your device. Cloud storage and share links are opt-in per project.
Can I use Caddis offline?
Local review is designed to work on your device. Cloud sync and share links naturally require an internet connection.
Which CAD formats can Caddis open?
Caddis opens supported geometry from DWG, ASCII DXF, STL, OBJ, PLY, STEP/STP, and IFC files. DWG, STEP/STP, and IFC compatibility is limited by source version and geometry type; unsupported geometry is reported rather than silently replaced.
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