3MF Viewer
Open and inspect 3MF files directly in your browser. Explore objects, components, colors, dimensions and declared units without uploading your model.
Your 3MF stays on this device. MeshWrench reads and renders it locally in your browser.
Up to 150 MB. Base-material and color-group colors are shown directly from the package; textures and other extensions are detected but not rendered.
Processed locally — nothing was uploaded.
- File size
- Package entries
- Declared unit
- Unit → millimeter scale
- Width (declared unit)
- Height (declared unit)
- Depth (declared unit)
- Width (mm)
- Height (mm)
- Depth (mm)
- Bounding min (mm)
- Bounding max (mm)
- Mesh objects
- Component objects
- Build items
- Resolved instances
- Source vertices
- Rendered triangles
- Base materials
- Color groups
- Texture resources
- Metadata entries
3MF declares a real measurement unit. Dimensions above are shown as declared and converted to millimeters — the conversion is applied once, using the file's own declared unit.
Build items & instances
How to view a 3MF file
- Select a 3MF file using the picker above.
- MeshWrench opens the package locally, in a background worker — nothing leaves your device.
- Once resolution finishes, drag to rotate, scroll to zoom, and use the panel below the viewport to fit the view, toggle wireframe, switch color mode, or show and hide individual build items and instances.
What the 3MF Viewer displays
After a file loads, the panel below the viewport shows file size, package-entry count, declared unit and its millimeter conversion factor, model dimensions in both the declared unit and millimeters, mesh/component object counts, build-item and resolved-instance counts, source vertex and rendered triangle counts, and base-material, color-group and texture-resource counts. A build tree lists every build item and resolved instance so you can inspect — and individually show or hide — the pieces of a multi-object model.
Objects, components and build items in 3MF
3MF organizes geometry differently from other formats this viewer supports: a mesh object holds real geometry, a component object references other objects (optionally nested, each with its own transform), and the build list places one or more instances of an object into the final scene. This viewer walks that real structure — build item → component instance → ...nested component instance → mesh object — rather than inventing object/group boundaries the way OBJ's viewer has to. A single mesh object referenced by several build items or components renders as several separate, independently visible instances.
How 3MF units are displayed
Unlike STL and OBJ, 3MF declares a real measurement unit — micron, millimeter, centimeter, inch, foot or meter. This viewer reads that declaration, shows dimensions in it directly, and also converts them to millimeters for reference. The conversion is applied exactly once, using the file's own declared unit — never guessed, and never applied twice.
How embedded colors are handled
3MF can declare colors through base-material resources and color-group resources, referenced by objects and individual triangles (including per-corner colors on a single triangle). "Embedded colors" mode reads and renders these directly from the package — no material or image file is ever fetched. "Neutral material" mode ignores color data on purpose, and "Color by object" mode uses a deterministic internal palette purely as a visualization aid, never presented as the file's real appearance. A file with no supported color data disables embedded-color mode automatically.
Why textures or extensions may not appear
Texture-based coloring, beam lattices, slice stacks and other 3MF extensions (production, volumetric, secure-content) are detected and disclosed with a clear warning, but this phase doesn't decode or render them — MeshWrench never fetches an external or cross-part resource to do so. Core mesh geometry still displays normally even when a file also uses one of these extensions.
3MF versus STL
3MF is a ZIP-based, XML-described format that can carry real units, colors, materials, named objects and a build structure with multiple placed instances. STL stores only raw triangle geometry, with no units and no metadata at all. This viewer can show 3MF's richer structure that a converter's flat STL output can't carry over.
Why a 3MF file may not open
- The package isn't a valid ZIP archive, or its internal relationships don't point to a model part.
- The model XML is malformed, or references an object, material or color index that doesn't exist.
- A component reference forms a cycle, or nests deeper than this tool's safety limit allows.
- The build list is empty, or resolves to no renderable geometry at all.
- The file is more complex (vertices, triangles, objects or instances) than this tool's safety limits currently allow.
Is the 3MF uploaded?
No. There is no server-side file-processing route in MeshWrench at all. Your browser reads the package, resolves its ZIP entries, parses its XML, and renders the result with WebGL — all on your device. You can verify this yourself: open your browser's developer tools, watch the network tab, and load a file. No request containing your file, or any path or metadata found inside it, will appear.
Frequently asked questions
Is my 3MF file uploaded?
No. The file is read and resolved entirely in your browser, inside a background Web Worker. It's never sent to a server — check your browser's network tab while a file loads to confirm this yourself.
Does this viewer show the file's real colors?
When a file uses 3MF's own base-material or color-group resources, yes — "Embedded colors" mode reads them directly from the package, with no image or material file fetched from anywhere. Textures (image-based coloring) are detected and reported, but not decoded or rendered in this phase.
What unit are the dimensions shown in?
3MF files declare a real measurement unit (micron, millimeter, centimeter, inch, foot or meter). This viewer shows dimensions in that declared unit and converts them to millimeters for reference — the conversion is applied once, using the file's own declared unit, never guessed.
Does this tool repair or validate my 3MF file?
No. This is a viewer only — it doesn't check for holes, non-manifold edges or flipped normals, and it doesn't modify your geometry in any way.
Does it render beam lattices, slice stacks or textures?
No. Those and other 3MF extensions (production, volumetric, secure-content) are detected and disclosed with a warning, but this phase doesn't decode or render them. Core mesh geometry still displays normally when a file also uses one of these extensions.
Which browsers are supported?
Any recent version of Chrome, Firefox, Safari or Edge with WebGL and Web Worker support.