What is a .USYM file?
.USYM is a Unity / IL2CPP file (Games). Analyser identifies a .USYM file and reads the metadata in its header, right in your browser.
- Did you know
- When Unity builds with IL2CPP it converts C# to C++ and compiles to native code, losing the method names a crash report needs.
- A .usym symbol file maps those native addresses back to the original C# methods, so a crash reads as a meaningful stack trace.
- Crash-reporting services like Sentry and Backtrace ingest .usym files to symbolicate Unity IL2CPP crashes.
- What Analyser reads
- Identify and read Unity engine files, including IL2CPP-compiled games: the IL2CPP symbol map (.usym - version, symbol count) and global-metadata.dat (magic-gated - metadata version, mapped to a Unity release), Addressables binary catalogs (catalog.bin, content-gated) and their catalog.hash, ShaderLab shaders (.shader) and shader variant collections (.shadervariants), asset bundle manifests (core_assets.manifest), renamed .NET metadata blobs (.pd_ - BSJB runtime version) and House Flipper photo thumbnails (.hfthumb - JPEG wrapped, re-openable as an image). Plus generic hash/checksum text (.hash).
- Depth of analysis
- .USYM is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .USYM file
- Drag a .USYM file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.
- Related formats
- .PD_ · .SHADERVARIANTS · .SHADER · .HFTHUMB · .HASH. See all supported file types.