Free online VRM to 3MF converter

3MF is required by many 3D-printing slicers and manufacturing workflows, while VRM is designed for animated humanoid avatars rather than fabrication. Converting the file therefore requires turning its rigged, pose-driven model into static, printable geometry.

What the VRM format is

VRM is an avatar format based on glTF 2.0. It packages humanoid meshes, an armature, skin weights, facial blend shapes, materials, textures, metadata, and often spring-bone behavior in one file.

VRM files are commonly created by VRoid Studio, exported from Unity projects through the UniVRM package, or edited with Blender using a VRM add-on. They are used in VTubing, virtual worlds, games, motion capture, and avatar viewers. A VRM model can change shape with animation, facial expressions, and physics, so it is not automatically a suitable static printing mesh.

What the 3MF format is

3MF is a ZIP-based 3D manufacturing format that stores one or more meshes together with units, transforms, colors, materials, and optional print metadata. Slicers such as PrusaSlicer, Bambu Studio, and UltiMaker Cura can use it for 3D-print preparation, although support for advanced 3MF metadata varies between applications.

Compared with a basic STL, 3MF can preserve multiple objects, units, colors, and printer-oriented project information without relying on ambiguous scale conventions. It is useful after the avatar has been reduced to printable, static geometry; it does not preserve VRM animation, bones, blend shapes, spring bones, or avatar metadata in a usable form.

How to actually convert VRM to 3MF

Desktop workflow with Blender and a slicer

1. Install Blender and a current VRM importer such as the VRM Add-on for Blender. Match the add-on version to your Blender release.
2. Import the model with File → Import → VRM. If the importer accepts only glTF, use a VRM-compatible importer rather than renaming the extension; changing .vrm to .gltf does not convert the file.
3. Select the avatar armature and choose a usable pose. Apply the pose through the armature pose controls, then convert the result to static geometry if necessary with Object → Convert → Mesh. Keep a backup of the original rigged model.
4. Delete non-printing objects such as cameras, lights, hair physics controllers, colliders, empty objects, and hidden helper meshes. Decide whether facial expression meshes, eyelashes, clothing layers, and accessories should be printed as separate parts or merged.
5. Inspect every mesh in Edit Mode. Recalculate normals with Mesh → Normals → Recalculate Outside, remove internal or duplicated faces, close open boundaries, and apply transforms with Object → Apply → All Transforms.
6. Give thin surfaces printable thickness with a Solidify modifier or by remodeling them. Hair strands, eyelashes, clothing edges, and detached fingers often fall below a printer’s minimum wall or feature size.
7. Check the model for non-manifold geometry using Blender’s 3D Print Toolbox add-on. Repair intersections and holes before export. A slicer may reject or reinterpret open shells.
8. Export an intermediate mesh through File → Export → Wavefront (.obj) or File → Export → STL. OBJ is preferable when separate objects, vertex colors, or texture references are still needed; STL is sufficient for a single monochrome solid.
9. Open the exported mesh in PrusaSlicer or Bambu Studio. Set the correct unit scale, orient the parts, check the layer preview, and repair or split objects if the slicer reports errors.
10. Save the prepared model with File → Save Project, which creates a slicer 3MF project, or use the application’s 3MF export command when available. Verify the saved .3mf by reopening it in the intended slicer.

Online conversion

You can also use the free converter on 101convert.com without installing software. This is suitable for a quick format change when the service accepts the particular VRM variant, but inspect the resulting 3MF in a slicer: automatic conversion may leave the avatar rigged, preserve non-printing parts, lose textures, or produce non-manifold surfaces.

Quality, compatibility, and limitations

The conversion is fundamentally lossy. 3MF does not reproduce VRM animation, humanoid bone mappings, blend-shape expressions, spring-bone physics, licensing metadata, or runtime avatar behavior. Select and apply one pose before exporting; otherwise the printed result may use the model’s bind pose or an unintended deformation.

VRM materials can use toon shaders, transparency, culling, and texture effects that have no direct 3D-print equivalent. A 3MF may retain color data only if the target slicer and printer workflow support it; transparent hair and alpha-masked clothing usually need opaque remodeling or manual cleanup.

Confirm scale in Blender and the slicer. VRM and glTF commonly represent distances in meters, while many mesh workflows interpret imported coordinates as millimeters. A factor-of-1000 error can make the model microscopic or enormous. Use a known reference dimension and inspect the slicer’s measured size before saving.

A 3MF saved by a slicer can contain printer profiles, supports, layer settings, and multiple meshes, so it may not open identically in another slicer. For interchange, save a clean model-only 3MF when the software provides that option and retain the repaired OBJ or STL as a fallback.