Extract text from LEGO designs (LDD)
To convert LDD designs to another format, you need LEGO Digital Designer or other 3D software.
To convert other file formats to the "Virtual Construction File" file type, you need software like LEGO Digital Designer or a similar tool.
The .LDD extension primarily represents 3D model files created by the now-discontinued LEGO Digital Designer. While this tool was once the standard for digital building, its abandonment has left many users with legacy files that are difficult to edit or render in modern workflows. The native format is a compressed archive containing an LXFML structure, which is proprietary and notoriously difficult to parse without specific tools. Users often face friction when trying to migrate these models into modern alternatives like BrickLink Studio or general 3D suites like Blender, as direct compatibility is often buggy or requires intermediate steps. For modern rendering, archiving, or 3D printing, converting .LDD to open standards like LDR (LDraw), IO, or mesh formats like OBJ and STL is essential.
A secondary, niche use case involves Brüel & Kjær (now HBK) dynamic data log files. These are specialized binary containers used in industrial settings to store noise and vibration measurement data gathered by Pulse LabShop software. These files are distinct from the 3D models and are heavily locked down, often exceeding 100MB in size and requiring expensive, proprietary licensing just to view the raw signal data. For these, the primary conversion goal is usually CSV or MAT (Matlab) for analysis.
Convert.Guru analyzes your LDD file, detects the exact format, and lets you read the text inside.
If you want to convert LDD file to , you can use LEGO Digital Designer or similar software from the "LEGO Model Project" category. In the File menu, look for Save As… or Export….
To convert files to LDD, try LEGO Digital Designer or another comparable tool in the "LEGO Model Project" category.
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our LDD converter.