Free online IGS to GLB converter

CAD data delivered as .igs must be converted when a web viewer, AR application, glTF pipeline, or other real-time renderer requires .glb. The process tessellates engineering surfaces into triangles and packages the result for display rather than CAD editing.

What IGS files contain

IGS, also called IGES (Initial Graphics Exchange Specification), is a legacy CAD interchange format used to exchange 2D drawings and 3D geometry between engineering systems. It can contain curves, NURBS surfaces, trimmed faces, boundary-representation solids, layers, colors, and annotations.

IGES remains common in supplier and legacy mechanical-data workflows, although STEP is generally preferred for newer CAD exchange because it preserves solid and product-structure data more consistently. CAD applications including CATIA, Siemens NX, PTC Creo, SolidWorks, Autodesk Inventor, Rhino, and FreeCAD can import IGES files, with supported entity types varying by application.

What GLB files contain

GLB is the binary form of glTF 2.0. It stores polygon meshes, scene hierarchy, PBR materials, textures, cameras, lights, skinning, and animations where those items are present in the source workflow.

Unlike an engineering model, a GLB is intended for rendering. A single .glb can package the glTF scene JSON, geometry buffers, and embedded images in one file, avoiding the separate files often associated with .gltf. This makes GLB suitable for web viewers and glTF-capable visualization pipelines.

Convert an IGS file to GLB

1. Open the IGS file in its source CAD system or a CAD viewer if possible. Repair missing faces, invalid trims, gaps, or failed solids before conversion; a mesh export cannot reliably repair defective CAD geometry.
2. On 101convert.com, upload the .igs file, select GLB as the output format, run the conversion, and download the .glb file. This can be done free of charge without installing software.
3. Open the resulting GLB in the intended viewer or application. Check dimensions, orientation, visible components, normals, and the smoothness of curved faces before deployment.

For an offline workflow, import the IGS file into FreeCAD, export a mesh such as .obj, then open that mesh in Blender. In Blender, use File → Export → glTF 2.0, set the format to glTF Binary (.glb), and export. Blender does not natively import IGES, so it is normally used for mesh cleanup and GLB export rather than the initial CAD import.

For large assemblies or close-up product rendering, use a desktop CAD translator that explicitly supports both IGES import and glTF 2.0/GLB export. Such tools may expose tessellation tolerances, assembly retention, material mapping, and part-name options that a basic conversion workflow does not.

Mesh quality and compatibility

The critical operation is tessellation: curved IGES surfaces are approximated by triangles. Coarse tessellation creates visibly faceted holes, fillets, and cylinders; excessively fine tessellation increases file size, GPU memory consumption, and loading time. Use tighter chordal and angular tolerances for close inspection and looser settings for distant or mobile viewing.

IGES unit information can be absent or interpreted inconsistently. glTF uses meters for linear distances, so CAD data authored in millimeters or inches may appear at the wrong scale. Measure a known feature after conversion and correct scale before publishing the GLB.

GLB does not retain editable CAD features, NURBS definitions, sketches, tolerances, manufacturing annotations, or parametric history. Keep the original .igs file and, where available, the native CAD model for engineering changes and archival storage.

Colors may transfer, but IGES color assignments do not map directly to glTF's physically based materials. Textures, transparency, part names, layers, and assembly hierarchy can also be omitted, flattened, or merged depending on the importer and exporter. Verify individual components when the GLB will support selection, animation, BOM matching, or separate material assignment.