A DGN file is a proprietary file format from Bentley Systems that is used in its CAD software solutions such as MicroStation, among others. MicroStation, and thus DGN files, are mainly found in areas such as construction, architecture and infrastructure, where they play an important role in CAD design.
Tip: As a verified Bentley Gold Channel Partner, coupled with many years of expertise in project management for construction and engineering projects, we support you in choosing suitable platforms as well as in efficient data management and process optimization. We help you find the right software solution for your individual use case!
Key Takeaways
This article covers the technical basics and background of the DGN format and its special significance for certain industries. It also covers practical aspects: viewing and opening DGN files (even without MicroStation) and the impact on collaboration in teams and between departments (e.g. at different locations).
The importance and advantages of the DGN format in CAD design
The DGN (.dgn) file format is one of the standard formats for technical drawings and design models. As a proprietary format, it is directly linked to well-known Bentley software solutions such as MicroStation and Navigator.
The main advantage of the DGN format is that it can efficiently manage large and complex data volumes. A DGN file offers high accuracy and flexibility when creating complex design models. This mix ensures that DGN files are often found in large-scale infrastructure projects, where precise models are of central importance. In addition, DGN files support 2D and 3D designs, which leads to a wide range of possible uses.

The basics: Software for opening a DGN file
The easiest way to open a DGN file is of course to open it and then use it in MicroStation. In this, you can not only open and view the files, but also edit them completely. DGN files can be opened and at least viewed without Bentley software. Here are some interesting alternatives, sorted by category:
Freeware and open source programs:
- Bentley View – free tool for viewing DGN files
- LibreCAD: CAD program (open source) that can display DGN files, but the functionality is significantly limited compared to MicroStation
Web-based solutions:
- Autodesk A360: a DGN file can be uploaded, opened and displayed, but there are no comprehensive editing features
- Other CAD software:AutoCAD: using plug-ins and/or conversion tools, AutoCAD can convert, open and edit a DGN file
Consequences for CAD process and collaboration
The DGN format itself is tried and tested and widely used, so far so good. However, challenges can arise if different software solutions are used within a team, between different departments or in cooperating companies. In practice, this is more common, because complex, large projects usually mean many people involved!
Smooth collaboration is still possible, but there are important aspects to consider:
- Interoperability / compatibility: if different CAD programs come together in a project, compatibility is crucial! In this context, it may be necessary to convert DGN files into other formats such as DWG (AutoCAD) or STEP
- Cloud-based collaboration: useful cloud solutions such as the iTwin platform (Bentley Systems) enable shared use and real-time collaboration on DGN files
- Versioning / data management: a large number of CAD data in a project are not conceivable without professional handling of file versions, which is why Bentley Systems offers in-house solutions such as ProjectWise (a central platform for data management and collaboration)
Power tip: If you work with CAD data and already use ELO as an enterprise content management (ECM), we recommend using our tailor-made software solution CME BElink2ELO. This gives you a solution that is just as powerful as ProjectWise, but with advantages in terms of cost-effectiveness and usability. With CME BElink2ELO you have the option of “viewing” your DGN files directly in the ELO document preview!
FAQ: All the advantages and disadvantages of a DGN file
Advantages:
- Precision / attention to detail: a DGN file enables precise design models
- Large data volumes: the focus on large data volumes makes it ideal for large infrastructure and construction projects
- Seamless integration: as a proprietary file format, DGN files interact with all Bentley Systems products, software solutions and services
Disadvantages:
- Proprietary format: the clear assignment to Bentley Systems can lead to challenges when integrating with other software solutions
- Limited support: proprietary formats such as DGN are only partially supported by third-party manufacturers, which limits the choice of compatible software accordingly
- Less widespread: DGN is de facto less widely used than other formats (e.g. DWG)
DGN files – and possible alternatives and open formats for exchange
CAD-FILE | INFOS | SOFTWARE |
DGN (Design) | native file format of Bentley Systems, primarily used in infrastructure planning and construction | MicroStationund Navigator, OpenRoads Designer |
DWG (Drawing) | native format of AutoCAD, widely used in construction and architecture | AutoCAD, DraftSight, BricsCAD, GstarCAD, Bentley Systems |
DXF (Drawing Exchange Format) | A file format developed by Autodesk for the exchange of CAD data between different programs | AutoCAD, SolidWorks, CorelCAD, QCAD, Bentley Systems |
STEP (Standard for the Exchange of Product Data) | an ISO standard format (ISO 10303) for the exchange of 3D models between different CAD systems | SolidWorks, CATIA, Siemens NX, Bentley Systems |
Conclusion
Complex infrastructure and construction projects = DGN files! This equation is undoubtedly true today, because the advantages of a DGN file in terms of precision and data volume are undisputed. For this reason alone, the DGN format plays a central role in CAD design today. The only real “disadvantage” is the proprietary nature of the file format and the logically limited compatibility that this entails, but this generally applies to all proprietary file formats.
In order to ensure optimal collaboration and efficient project processes, one should always be aware of the resulting challenges in the areas of interoperability and integration. Open exchange formats such as DXF and STEP can be part of the solution, depending on the project requirements. In general, it is a good idea for companies that focus on complex infrastructure and construction projects to think about Bentley Systems as their (main) software.