Click the "Select File" button above, and choose your ULD file.
You’ll see a preview, if available.
Click the "Convert file to..." button to extract text information.
Convert ULD to another file type
To convert ULD luminaire files to another format, you need DIALux or other Cad software.
Convert a file to ULD
To convert other file formats to the "Luminaire Photometric Model" file type, you need software like DIALux or a similar tool.
About ULD files
The .uld file is a Unified Luminaire Data format utilized primarily by DIALux, a leading lighting design software. These files store highly detailed 3D geometry of light fixtures paired with complex photometric data, such as light distribution curves and intensity. Internally, the format is structured as a Microsoft Compound Document. The primary software used to open and edit these files is DIALux. Lighting designers use this tool to simulate artificial and natural lighting in architectural environments. The major disadvantage of the .uld format is its proprietary nature. It creates severe vendor lock-in. You cannot open a .uld file natively in standard CAD software like AutoCAD or 3D modeling tools like SketchUp. It requires a hefty, specialized software installation just to view the light emission data or the physical fixture dimensions. Furthermore, web browsers and standard file explorers completely fail to preview these files. To achieve interoperability, users must convert .uld files into industry-standard formats. Photometric data is best converted to IES (Illuminating Engineering Society) or LDT (Eulumdat) files. For the physical 3D fixture model, converting to DXF or OBJ is highly recommended. Note that extracting data often splits the geometry from the light calculations. Because this is a closed, proprietary format, standard online converters fail to process it. We can parse the container to expose text metadata or extract standard underlying components if embedded within.
Convert.Guru analyzes your ULD file, detects the exact format, and lets you read the text inside.
If you want to convert ULD file to LDT, DWG, DXF, DGN, RVT, RFA, SKP, 3DM, STEP, IGES, SAT or X_T, you can use DIALux or similar software from the "Lighting Design Data Storage" category. In the File menu, look for Save As… or Export….
To convert SLDASM, DGN, PRT, IAM, X_B, CATPRODUCT, SLDPRT, RVT, ASM, DWG, CATPART or DXF files to ULD, try DIALux or another comparable tool in the "Lighting Design Data Storage" category.
The ULD Converter Story
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 ULD converter.