🏅 Convert 3DM to JSON: Rhino 3D to CityJSON Model Converter

How to Convert 3DM to JSON?

Follow this beginner-friendly step-by-step guide to convert 3DM to JSON accurately and efficiently using our dedicated conversion tool:

  1. 📥 Download and Install

    Download and install Autoconverter on your system. This application will let you to convert your 3DM files to JSON format - no additional CAD software required.

  2. 📂 Open Your 3DM File

    Go to File > Open… to load your 3DM file (*.3dm), or drag and drop it directly into the application window. The model loads into the 3D viewport for inspection before converting.

  3. 💾 Save As JSON Format

    Go to File > Save As…, select JSON (*.json, *.cityjson) as the output format, choose your destination folder and filename, then click Save to complete the 3DM to JSON conversion.

3DM Rhinoceros 3D (3DM) File Format

The 3DM file format is the native format for Rhinoceros 3D (Rhino), a leading NURBS-based 3D modeling software used across industries like architecture, engineering, and industrial design. 3DM files accurately store mathematical representations of curves, surfaces, solids, and meshes, making them essential for precision 3D modeling and CAD workflows.

Key Features of 3DM Files

  • NURBS Geometry: Supports precise, smooth surfaces critical for advanced design and engineering projects.
  • Polygonal Meshes: Stores tessellated 3D models ideal for rendering, simulation, and 3D printing workflows.
  • SubD Surfaces: Allows flexible, editable subdivision modeling for organic shapes and complex surfaces.
  • Instance References: Saves memory by creating linked object instances, optimizing large and detailed models.

Convert 3DM Files Seamlessly

Autoconverter and Autoshaper simplify 3DM file conversion to popular formats like STEP, IGES, OBJ, STL, and DWG. Automate the export of 3DM polygon meshes for 3D printing, or preserve NURBS data for engineering-grade CAD models. Save files in legacy (Rhino 2.X - 7.X) or latest Rhino 8.X formats to ensure compatibility across all project environments.

JSON 3D City Model (CityJSON) File

The CityJSON file format is a modern, JSON-based (JavaScript Object Notation) standard designed for storing and exchanging 3D city models. It efficiently encodes buildings, roads, bridges, urban furniture, and other city objects, offering strong support for textures, semantics, and detailed metadata. CityJSON is a lightweight alternative to CityGML, optimized for simplicity, web integration, and high-performance applications.

Key Features of CityJSON Files

  • JSON Simplicity: CityJSON files are lightweight, human-readable, and easily parsed by common programming languages, avoiding the complexity of XML structures like in CityGML.
  • Semantic Data: Preserves rich metadata, including building heights, roof shapes, material classifications, and road types, enhancing 3D GIS and urban analysis.
  • LOD (Level of Detail) Support: Manages multiple levels of detail (LOD1 through LOD4) to suit diverse visualization, simulation, and analysis needs.
  • Web-Friendly Format: Perfect for 3D web visualization and integration with JavaScript libraries like Cesium and Three.js.
  • Open and Extensible: Developed by the 3D Geoinformation Group (Delft University of Technology), CityJSON is an open standard that promotes interoperability and innovation.
  • File Extension Note: Both CityJSON and GeoJSON use the .json extension - ensure you verify the file structure before processing to avoid errors.

CityJSON File Conversion Made Easy

With Autoconverter and Automesher Application, you can seamlessly import, export, and convert CityJSON files into formats like STL, OBJ, SKP (SketchUp), and 3DS. Our tools preserve geometric precision and semantic information, making it easy to integrate 3D city models into your CAD, GIS, and 3D visualization workflows.

Streamline Your 3D City Modeling Today

Optimize your urban planning, GIS projects, and 3D web applications with powerful CityJSON file conversion. Try Autoconverter and Automesher Application now and unlock the full potential of CityJSON in your workflows!

3DM vs JSON - Comparison

The table below shows the differences between 3DM and JSON to guide your selection for 3D modeling, CAD, or GIS tasks.

Feature 3DM JSON
Extensions .3dm .json, .cityjson
Name Rhinoceros 3D Model CityJSON
Versions
  • Min: Rhino 2.x
  • Max: Rhino 8.x
🚫
Textures ✅ ✅
Colors ✅ ✅
Geometry Components ✅ ✅
User Attributes ✅ ✅
Quads ✅ ✅
Importers
Exporters

More 3DM and JSON Conversion Guides

Want a faster, easier approach to 3DM to JSON conversion? Our expert guides below show you exactly how 3DM files conversion is done:

👉 Tired of unreliable 3DM and JSON conversion tools? Switch to our 3DM to JSON converter for precise, consistent results and a smoother workflow every time.