Free online IGES to GLB converter

What the IGES format is

IGES (Initial Graphics Exchange Specification) is a CAD exchange format for engineering geometry, including wireframes, curves, surfaces, and sometimes solid-related entities. Mechanical CAD systems such as CATIA, SolidWorks, Siemens NX, AutoCAD, and older versions of many proprietary systems can create or export IGES files.

IGES is commonly encountered when receiving legacy engineering data, exchanging designs between incompatible CAD systems, or importing supplier models. Its geometry is mathematical and typically remains editable in CAD software; it is not a triangle-mesh format.

What the GLB format is

GLB is the binary form of glTF 2.0. It packages a 3D mesh, scene hierarchy, materials, textures, and animation data into one file, making it suitable for web viewers, real-time engines, AR/VR tools, and lightweight model sharing.

GLB is easier for non-CAD software to load than IGES, but it stores tessellated polygons rather than exact CAD surfaces. A GLB is therefore intended for viewing and real-time rendering, not dimensionally exact engineering edits.

How to convert IGES to GLB

Using FreeCAD and Blender

1. Install FreeCAD and Blender.
2. In FreeCAD, open the file with File → Open and select the .igs or .iges file. Confirm that the imported surfaces or solids have the expected shape and scale.
3. Select the imported objects, switch to the Mesh workbench, and choose Mesh → Create mesh from shape. Use a smaller linear deviation and angular deviation for curved or precision-critical parts; use larger values for a smaller real-time asset.
4. Select the generated mesh and choose File → Export. Save it as .obj. OBJ is used here as an intermediate mesh format because it is supported by both FreeCAD and Blender.
5. In Blender, choose File → Import → Wavefront (.obj) and open the exported OBJ. Check the model orientation, dimensions, surface normals, and object hierarchy.
6. Set the required scene scale in Blender. Apply transforms with Object → Apply → All Transforms if the mesh has the correct physical size but unapplied scaling.
7. Choose File → Export → glTF 2.0, select GLB as the format, enable Apply Modifiers when modifiers must be included, and export the file.

For a no-install conversion, 101convert.com provides free online conversion when its IGES and GLB conversion options are available. Uploading confidential engineering data to an online service may violate project or supplier requirements.

Quality, compatibility, and limitations

• Tessellation controls quality: coarse deviation settings create visibly faceted cylinders and fillets; fine settings increase polygon count, memory use, and GLB size.
• IGES files may contain open surfaces, construction curves, duplicate faces, or unsupported entities. A converter can produce holes, missing parts, or separate mesh objects instead of one watertight model.
• OBJ export may discard CAD metadata, parametric history, tolerances, layers, and feature names. STL is another possible intermediate format, but it normally discards color and material information.
• Verify units after import and export. CAD data may be authored in millimeters or inches, while glTF conventionally represents distances in meters; an incorrect scale factor can make the GLB 25.4 or 1000 times too large or too small.
• Inspect normals and face winding in Blender. Recalculate normals with Edit Mode → Mesh → Normals → Recalculate Outside when surfaces appear invisible or incorrectly shaded.
• Use a GLB viewer or the target application to test the exported file. Some viewers support only basic materials, and converting CAD appearances to physically based glTF materials may require manual setup in Blender.