> For the complete documentation index, see [llms.txt](https://autodesk.ifc-manual.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://autodesk.ifc-manual.com/understanding-ifc/ifc-viewers.md).
# IFC Viewers
IFC files should be reviewed in an IFC viewer after the export. Linking or opening the IFC file a BIM authoring software is not recommended for this purpose.
### Overview of free IFC viewers
[**viewer.autodesk.com**](http://viewer.autodesk.com) (free Autodesk viewer) supports 50+ file formats and allows sharing and commenting. Uploaded files are stored for 30 days by default, and can be deleted or extended as needed.
*Autodesk Solutions based on the same technology and free for AEC Collection Users:*
[**Autodesk Docs**](https://www.autodesk.com/campaigns/autodesk-docs) (included in the AEC Collection) is based on the same technology as the Autodesk Viewer, but offers some extended features for document and project management.
[**Autodesk Navisworks**](https://www.autodesk.com/products/navisworks/overview) (included in the AEC Collection) is the desktop coordination solution from Autodesk with extended features like 4D/5D Simulation and clash management.
*Selected third-party free IFC Viewers frequently used by Autodesk customers:*
[**Open IFC Viewer**](https://openifcviewer.com/) developed by Open Design Alliance (ODA), a very fast and advanced IFC viewer, supporting the latest IFC versions including IFC 4.3. Caution: this viewer might not always display custom Property Sets.
[**BIMvision**](https://bimvision.eu/) developed by Datacomp
[**BIMcollab Zoom**](https://www.bimcollab.com/en/products/bimcollab-zoom/) developed by BIMcollab
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