What is an IGR file?
An .IGR file is most commonly a 2D design and drafting file created by SmartSketch (formerly by Intergraph, now Hexagon). Engineers and designers use these files for precise technical drawings. Behind the scenes, these .IGR files are often saved using standard DOC (OLE Compound Document) structures or ZIP compression. However, the .IGR extension is shared by other completely different programs. It can also be an Igor Engraver File created by NoteHeads, a Quest3D Channel Group Layout File by Act-3D, or a graphics file for Innovyze InfoWater.
How to open IGR files?
To open an .IGR file natively, you usually need the specific software that created it. If you do not have SmartSketch or the other tools installed, viewer.online/igr analyzes .IGR files to identify their exact format and creator software, shows which programs can open the file, and usually previews it. If the file is a compressed archive, standard unzipping utilities can also extract its contents.
Software and tools
The dominant application for viewing and editing these drafting files is SmartSketch. If the file belongs to an alternative format, you might need legacy software like NoteHeads for musical notation or Quest3D for rendering layouts.
Summary
Because an .IGR file has multiple possible meanings, we recommend using viewer.online/igr to identify the actual format of your file. Because many .IGR files use the known DOC format structure, viewer.online/igr can safely open and display them online, eliminating compatibility problems.