Free Rhino 3DM viewer Open a Rhino .3dm model without Rhino - orbit around it, switch layers on and off, click objects to see their details, and save it as STL, OBJ or GLB - entirely in your browser
Report a problem or suggest something All design, 3D & maps tools
About this Rhino viewer Rhino (Rhinoceros 3D) saves its models as .3dm files. Jewellers, product designers, architects and boat builders use it, and Grasshopper scripts bake into it, so .3dm files turn up in client handovers, 3D printing jobs and student work. Opening one usually means installing Rhino or a trial, and most 3D tools - Windows 3D Viewer, Blender, slicers - can't read it.
This page reads the model with rhino3dm, McNeel's own open-source library for .3dm files, compiled to run in your browser. It draws the surfaces, meshes, SubDs, curves, points and text dots in their layer colours, lists the layers so you can switch them on and off, and places blocks where they belong. Click any object to see its layer, size and attribute user text. You can then save what is shown as STL for 3D printing, OBJ, or GLB. The file is read on your computer and never uploaded. It is free to use, with no account and no upload limit, and it runs entirely in your browser: nothing is uploaded, and while the page stays open, a feature you have already used keeps working offline. For STL, OBJ, PLY or GLTF meshes, use the 3D Model Viewer ; for STEP or IGES, the STEP Viewer .
What you can do Open .3dm files from Rhino 1 to 8, Grasshopper and other programs that write them Orbit, zoom and pan around the model in its layer and material colours Switch layers and sub-layers on and off, or show one layer on its own See polysurfaces, extrusions, meshes and SubDs, with curves, points and text dots See blocks placed where they belong, nested blocks included Click an object for its type, name, layer, size and attribute user text See the model's units, size, who made and last edited it, and with which version of Rhino Convert 3DM to STL (millimetres, for slicers), OBJ or GLB, and save the view as a PNG How to open a 3DM file without Rhino Drop the .3dm file onto the page, or click to choose it. The first file also loads the Rhino reader. Drag to turn the model, scroll to zoom, and untick layers to hide them. Click an object to see its details on the right. To use the model elsewhere, save it as STL, OBJ or GLB. Only what is shown is saved. Questions
Why are some of my surfaces missing? Rhino stores surfaces as exact NURBS maths and, beside them, a render mesh of triangles for display. This page draws the render meshes. A file saved with "Save small" (or with File, Save As and "Save geometry only") has none, so those surfaces can't be shown; the page tells you how many. Open the file in Rhino, untick "Save small" and save again, or export it as STL or OBJ.
How do I convert a 3DM file to STL for 3D printing? Open it here, switch off any layers you don't want printed, and choose Save STL. The STL is binary and in millimetres whatever units the model uses, which is what Cura, PrusaSlicer, Bambu Studio and other slicers expect. Its detail is that of Rhino's render mesh; for a finer print mesh, use Rhino's Mesh command before saving.
Can it open files from Rhino 8 and older versions? Yes. The reader handles every .3dm version from Rhino 1 to Rhino 8, so a file someone sends you opens here whichever version they use, without "save as" an older version first.
Can I open a Grasshopper .gh file here? No. A .gh file is a script, not a model: it only makes geometry when Grasshopper runs it. Bake the result into Rhino and save it as .3dm, and that opens here.
Is my Rhino model uploaded? No. The Rhino reader is downloaded to your browser and the model is read there, so a jewellery design, product or building under NDA never leaves your computer.