Minimalistic and simple file format for BIM


In one sentence: We transfer triangulated meshes with dictionary attached to it

  • Transfer geometry and data
  • Free and open
  • Make it possible to write tools for it in a couple of hours
  • 1 page documentation
  • Make sure all others can support all of its features
Main information
  • .bim
  • License MIT
  • JSON structure
  • x, y, z coordinates should be in meters
  • JSON objects and properties should start with lowercase and with underscore as a seperator between words, e.g. schema_version


Current version of schema is: "1.0.0"

Documentation is specified as a text file and also as a C# library.

Whole documentation is placed here: Github Repo


Libraries to work with .bim files
  • dotbim-archicad - .bim add-on for Archicad: Github Repo <- Author: Viktor Kovacs
  • dotbimGH - Grasshopper plugin: food4rhino
  • dotbim-blender - .bim add-on for Blender: Github Repo <- Author: Nathan Hild
  • SketchUp add-on: Github Repo <- Author: Mattia Bressanelli
  • Revit detailed MEP to schematic 3d model: Github Repo <- Author: Yoann Obry
  • dotbim-ifc - IFC Converter: Github Repo <- Author: Dion Moult
  • dotbim-io-dxf: Github Repo <- Author: Nathan Hild
Viewers that support .bim files
  • Online 3d Viewer: https://3dviewer.net <- It also provides tools to convert .bim into other files like .obj, .stl, .ply, .gltf, .glb, .off, .3dm Authors: Viktor Kovacs, Agnes Gaschitz

If you're working on some tools or viewers for .bim files: let me know I'll place it there ;)


If you need code examples to start to work with it: check out Apps section and libraries. Inside these libraries you will find code examples :)

Test files can be taken from the repo here: Example files

Here below you will find some of them. CLICK the blue icon to open it in new tab with Online 3d Viewer and explore properties attached to elements after selecting them.

  • Multilevel BIM example by Robert Juchnevic created with Blender. Click on the blue icon to explore it more.
    Read more about Linking data presented in the model here: Linking data with .bim
  • Bridge example by Marcin Woch created with Grasshopper
  • Room example by Viktor Kovacs created with Archicad
  • Examples created by conversion from IFC


  • structuralbasics.com / 06.06.2022 / Dotbim: Export a 3D model from Grasshopper as .bim format / Read
  • BIM Corner / 04.05.2022 / .bim - a new BIM file format / Read
  • BIMvoice - podcast / 01.04.2022 / dotbim – Minimalist File Format for BIM with Wojciech Radaczyński / Watch
  • osarch.org / 26.02.2022 / dotbim – minimalist file format for BIM / Read


  • Multicolor extension Github Repo <- Author: Viktor Kovacs


You can mail me directly here: w.radaczynski@gmail.com