What is an .LLM file?
An .LLM file can be one of several different 3D data formats. The most common use is a Linden Lab Mesh File developed by Linden Research for the Second Life virtual world. These are binary avatar mesh files used to store 3D character shapes and clothing. Another common use is for material or decal files associated with Quixel NDO software. Finally, some .LLM files contain labeled Laser Measurement data from 3D scanning applications like Polycam.
How to open .LLM files?
Because an .LLM file can contain different types of data, the correct software depends on its origin. If the file is a Linden Lab Mesh File, you can use the Second Life Viewer or compatible third-party viewers like Firestorm. If the file is a 3D material, you will need Quixel NDO or Quixel Suite. For laser measurement data, use Polycam or a compatible point-cloud viewer.
Best practices and troubleshooting
If you double-click an .LLM file and your computer does not know how to open it, you must first identify the exact format. Do not rename the file extension to another 3D format like .OBJ or .FBX, as this will not convert the binary data and will corrupt the file. Instead, use a file inspection tool to read the file headers and determine which software created it.
Software and tools
Summary
viewer.online/llm can analyze .LLM files to identify the exact format and creator software, inspect the file structure, extract readable text, and check whether an online preview is available. Because this extension has multiple possible meanings, viewer.online/llm is useful for identifying, inspecting, and understanding .LLM files without installing software or dealing with compatibility problems.