Free online IGS to GLTF converter

What the IGS format is

IGS, usually stored with the .igs or .iges extension, is the file format defined by the Initial Graphics Exchange Specification. It exchanges CAD geometry between systems, including trimmed surfaces, wireframes, curves, and sometimes solid models.

Mechanical CAD programs such as CATIA, Siemens NX, Solid Edge, SolidWorks, Autodesk Inventor, and older versions of AutoCAD can create or import IGES files. You commonly encounter IGS files when receiving legacy engineering data from a supplier or moving geometry between different CAD systems.

What the GLTF format is

glTF is a runtime 3D format designed for efficient delivery and rendering. A model may use a binary .glb file, which contains geometry, materials, textures, and scene data in one file, or a .gltf JSON file accompanied by binary and image resources.

It is supported by WebGL viewers, game engines, augmented-reality tools, and many browser-based 3D libraries. Compared with IGES, glTF is better suited to visualization and distribution, but it does not preserve exact parametric surfaces, sketches, feature history, or editable CAD constraints.

How to actually convert IGS to GLTF

Using the built-in online converter

1. Open the IGS-to-GLTF converter on 101convert.com.
2. Upload the .igs or .iges file.
3. Choose GLTF as the output format. Choose GLB instead if the destination accepts a single packed file.
4. Start the conversion and download the generated file when processing finishes.

This option requires no installed CAD or 3D software. Upload limits, supported assembly structures, and texture handling depend on the converter implementation.

Using desktop CAD conversion software

CAD Exchanger is a practical desktop option when the model contains assemblies or when tessellation settings need adjustment:

1. Open CAD Exchanger and select File → Open, then choose the IGS file.
2. Check the imported body count, units, surface orientation, and assembly hierarchy in the model tree.
3. Select File → Save As or the export command and choose GLTF or GLB.
4. Set the mesh deviation or tessellation quality if the export dialog provides it. Use a smaller deviation for curved or precision-critical visual models, and a larger deviation for lightweight web delivery.
5. Open the result in a glTF viewer to check scale, missing faces, materials, and textures.

Exact menu names and available export settings vary by CAD Exchanger version and license. A CAD application that imports IGES and exports glTF can be used similarly, but confirm both capabilities before relying on it; many CAD programs export STEP, STL, or OBJ without offering glTF.

Quality, compatibility, and limitations

IGES stores mathematical CAD surfaces; glTF stores triangulated mesh geometry. The conversion therefore depends on tessellation tolerance. Coarse tessellation produces visibly faceted cylinders and fillets, while very fine tessellation increases polygon count, file size, and browser rendering cost.

IGES files frequently lack reliable material, color, texture, and assembly metadata. A converter may preserve basic face colors but cannot recreate appearance data that is absent from the source. Check units after export because IGES unit interpretation can vary, while glTF uses meters as its standard unit.

Use .glb when the recipient expects one portable file. A .gltf export may reference separate .bin and image files; keep those files together and preserve their relative paths. glTF is not a substitute for a native CAD archive: retain the original IGS file when exact geometry or later engineering edits matter.