Free Online IGES Viewer (No Signup)
Also opens DWG, DXF, STEP, IGES, SKP, STL, OBJ, GLB, FBX, 3DM and other 3D/CAD files — drop any file on the viewer.
Works in Chrome, Firefox, Safari, and Edge — no plugin required
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What Is a IGES File?
IGES (.igs / .iges) is the elder statesman of CAD interchange — an ANSI standard from 1980 and, for two decades, the default way to send geometry from one CAD package to another. It is a plain-text, fixed 80-column format organized into Start, Global, Directory Entry, Parameter Data, and Terminate sections. Rather than triangles, it stores exact geometry: NURBS curves and surfaces, trimmed surfaces, B-rep solids, wireframe entities, points, and annotations.
Because there are no triangles in the file, viewing IGES means evaluating and tessellating its NURBS surfaces — the same heavy geometry-kernel work a STEP file needs. If you’ve received an .igs or .iges file from a supplier, machine shop, or older CAD system, this viewer opens it in your browser — no CATIA, NX, or converter required.
Who Uses IGES Files?
IGES is still everywhere in aerospace, automotive, marine, and tool & die work, where it remains a contractually required deliverable long after STEP became the modern default. Heavyweight CAD systems — CATIA, NX, Creo, SolidWorks, and Inventor — all export it, and translators such as DATAKIT and Theorem write it for downstream CAM, inspection, and analysis tools that only speak IGES.
Common Use Cases
- Open an .igs / .iges file from a supplier or machine shop without CAD installed
- Quickly check a surface model received from a CATIA, NX, or Creo user
- Verify an IGES export before sending it on to a CAM or inspection tool
- Convert IGES to STL for 3D printing, or to GLB for the web
- Generate a PDF snapshot of the model for a quote or submittal
- Share a link to a 3D model without making the recipient install a CAD viewer
Features
Open Instantly
Drag and drop a .igs or .iges file — it tessellates and renders in your browser using the OpenCASCADE geometry kernel.
True NURBS Surfaces
Reads exact NURBS curves, trimmed surfaces, and B-rep solids the way professional CAD tools do — not a pre-baked mesh.
3D Navigation
Orbit, pan, and zoom with mouse or touch to inspect every surface and face.
Live Load Progress
Large IGES files take time to tessellate; an elapsed-time counter and live status keep you informed.
Per-Face Rendering
B-rep faces render as distinct surfaces, so the model reads the way it does in CAD.
Convert to STL
Export a triangulated STL mesh ready for 3D printing, CNC, or simulation.
Convert to GLB
Export your IGES as a GLB file — the universal 3D format for Blender, Unity, and the web.
Convert to OBJ
Save as Wavefront OBJ for use in 3ds Max, Maya, Cinema 4D, and other tools.
Export as PDF
Save the current view as a clean PDF — ideal for quotes, submittals, and design reviews.
No Upload Required
Your IGES file is parsed entirely in your browser. Nothing leaves your computer.
Embed on Any Site
Add the IGES viewer to your website with a single iframe embed code.
Compatibility & Format Notes
This viewer tessellates IGES with Open CASCADE Technology (via the open-source occt-import-js WebAssembly build), the same geometry kernel that powers FreeCAD — so it reads NURBS surfaces, trimmed surfaces, and B-rep solids the way professional CAD tools do.
IGES files that contain only wireframe curves, points, or 2D drafting entities have no surfaces to shade and will report that there is nothing to display — re-export with surface or solid geometry. Large IGES models carry a lot of surfaces and can take up to a minute to tessellate; the loading screen shows live progress while it works.
Embed on Your Website
Add this viewer to your own site with a single line of HTML. Click Embed in the toolbar to generate an embed code, or use the snippet below with your own file URL.
Your Files Stay on Your Computer
Your IGES files are parsed entirely in your browser. Nothing is uploaded, stored, or shared unless you explicitly click the Share button. Shared files are hosted for 90 days then deleted.
Frequently Asked Questions
▶What is the difference between IGES and STEP?
Both are neutral CAD interchange formats. IGES (1980) is older and surface-centric; STEP (ISO 10303, 1994) is newer, carries richer solid-model and assembly/product data, and is the modern default. Many industries still require IGES for legacy compatibility. This viewer opens both through the same OpenCASCADE engine.
▶Do I need CATIA, NX, or other CAD software to open an IGES file?
No. This free online viewer reads .igs and .iges files directly in your browser using the open-source OpenCASCADE kernel compiled to WebAssembly. Nothing is installed and nothing is uploaded.
▶Why does my IGES file take a while to open?
IGES stores NURBS surfaces, not triangles, so the viewer has to evaluate and tessellate every surface before it can draw anything. A large file (tens of MB, thousands of surfaces) can take up to a minute. The loading screen shows an elapsed-time counter and live status so you can see it is still working.
▶My IGES file says there is nothing to display — why?
That means the file contains only wireframe curves, points, or 2D drafting entities — there are no surfaces or solids to shade. Open it in your CAD system and re-export with surface or solid geometry included.
▶Can I convert IGES to STL or STEP?
You can export the tessellated model to STL (3D printing), OBJ, GLB (glTF binary), or PDF from the toolbar. Converting to STEP is not offered here — for that, re-export from your CAD system, which preserves the exact NURBS geometry rather than a tessellated mesh.
▶Is this IGES viewer really free?
Yes, completely free. No signup, no watermarks, no file size limits on the viewer (the optional share-link feature has a 30 MB upload cap). Built by Innerscene as a tool for architects, engineers, and designers.
▶Are my files uploaded to a server?
No. All parsing, rendering, and conversion runs in your browser — nothing is uploaded, stored, or transmitted by default. The Share button is the only feature that uploads a file, and only when you explicitly click it.
▶Can I convert to another format?
Yes. Click Export in the toolbar to save as STL (3D printing), OBJ (Wavefront), GLB (glTF binary), or PDF (snapshot of the current view).
▶Can I embed this viewer on my own site?
Yes. Click Embed in the toolbar to generate a one-line <iframe> snippet you can paste into any HTML page. You can choose whether the embed shows the viewer’s toolbar.