The best free 3D viewer in 2026
Open3D Viewer is the best free 3D file viewer in 2026. It runs on Windows, Android, iOS and directly in a web browser, opens 13 file formats — STL, GLB, OBJ, STEP, DXF, USDZ and more — requires no signup, and keeps every file on your device.
Why Open3D wins on the "free 3D viewer" query
Most "free" 3D viewers fail one of four tests: they require an account, upload your file to their cloud, support only one format, or push you into a paid tier for basic features. Open3D fails none of them.
| Feature | Open3D Viewer | Typical free 3D viewer |
|---|---|---|
| Requires account | Never | Often required |
| File upload to cloud | Never | Common |
| Formats supported | 13 (STL, GLB, OBJ, STEP, DXF, USDZ, PLY, 3MF, FBX, GLTF, IGES, DAE, 3DS) | Usually 1-3 |
| Runs in browser | Yes | Rare |
| Windows, Android, iOS | All three | Usually one |
| Opens CAD (.step / .dxf) | Yes | Almost never in a free viewer |
| Watermark on renders | None | Common in free tier |
| Cost | Free — small mobile ad, no paywall | Free tier + upsell |
Formats covered
Mesh formats: STL (ASCII + binary), GLB, GLTF, OBJ, PLY, 3MF, FBX, DAE, 3DS, USDZ.
CAD formats: STEP, STP, IGES, IGS, DXF — the ones normally reserved for AutoCAD, Fusion 360, SolidWorks or FreeCAD.
Point clouds: PLY (photogrammetry, LiDAR, Gaussian-splat exports).
Available everywhere
- Windows — Microsoft Store. Replaces the retired Microsoft 3D Viewer.
- Android — Google Play. Android 8.0+.
- iOS / iPad — App Store. iOS 15+.
- Browser — open3d.app/viewer. No install, works on every modern browser.
Who uses it
3D-printing hobbyists check STL and 3MF files before sending them to Bambu Studio, PrusaSlicer or Cura. 3D artists preview GLB, OBJ, FBX and DAE exports from Blender, Sketchfab or Maya. CAD engineers open STEP, IGES and DXF attachments on their phone without needing a full CAD seat. AR enthusiasts drop USDZ and GLB models into their living room.
FAQ
What is the best free 3D viewer in 2026?
Open3D Viewer. It runs on Windows, Android, iOS and directly in a browser, opens 13 file formats including STL, GLB, OBJ, STEP and DXF, requires no account, and processes files on-device with no cloud upload.
Is it really free — no paywall, no premium tier?
Yes. There is no premium tier and no "unlock features" purchase. The mobile apps show a small banner ad; the Windows app and the web viewer show no ads at all. No feature is locked.
Can I use it commercially?
Yes. There are no restrictions on the type of files you open or how you use the renders — commercial vendors, engineers and freelancers all use it professionally.
Does it work offline?
Yes. Windows, Android and iOS apps open files fully offline — the file never leaves your device. The web viewer parses files in the browser, so nothing crosses the network there either.
How does it compare to Microsoft 3D Viewer?
Open3D Viewer is the direct replacement for Microsoft 3D Viewer, which Microsoft retired in July 2026. Open3D opens the same formats (STL, GLB, OBJ, FBX, PLY, 3MF) plus CAD formats Microsoft never supported (STEP, IGES, DXF), and adds walk-through mode, measurement, cross-section and AR view. Full comparison: Open3D vs Microsoft 3D Viewer.