.XB file extension
To open .XB files on Windows, install XMOS XTC Tools (v15.3 documentation covers the relevant xobjdump behavior).
To open a .xb file, treat it as an XMOS XE-related output and use the XMOS XTC Tools (notably xobjdump) on a desktop OS. If you expected a 3D CAD file, note that Parasolid binaries usually use the extension .x_b (with an underscore), not .xb.
Last updated: October 13, 2026
Open on your device
Choose your operating system for a dedicated step-by-step opening guide.
How to open .XB files
Use these platform-specific instructions to open .XB files safely.
Windows
- Install XMOS XTC Tools (v15.3 documentation covers the relevant xobjdump behavior).
- Open a Command Prompt and run xobjdump against the .xb file to inspect or process it (use xobjdump options appropriate for your workflow, since the .xb is an XE-derived output created by xobjdump).
Mac
- Install XMOS XTC Tools for your environment (use the XTC Tools documentation as the reference for your version).
- In Terminal, run xobjdump on the .xb file to inspect contents or generate needed outputs.
Linux
- Install XMOS XTC Tools (the xobjdump manual describes creation and handling of .xb-suffixed XE output).
- In a shell, use xobjdump with the relevant options on your .xb file to inspect or convert it.
iOS
- There is no typical iOS app support for XMOS .xb (XE-derived) files; transfer the file to a desktop OS and use XMOS XTC Tools (xobjdump).
Android
- There is no typical Android app support for XMOS .xb (XE-derived) files; transfer the file to a desktop OS and use XMOS XTC Tools (xobjdump).
Security notes
- .xb files in the XMOS context are part of an executable/toolchain pipeline (XE/ELF-derived). Treat them as potentially executable firmware artifacts and only use them if you trust the project/source.
- Even if you do not execute them directly, opening untrusted .xb files with binary-parsing tools (like dump/analysis utilities) can expose you to parser vulnerabilities; prefer running such tools on trusted inputs or in a constrained environment.
- Do not assume .xb is a CAD exchange file: mixing up XMOS .xb with Parasolid .x_b can cause you to use the wrong toolchain and mis-handle untrusted binaries.
Can't open this file?
These are the most common causes and fixes when .XB files fail to open.
Common reasons
- The file won’t open in CAD/3D software
- Windows asks which app to use / ‘Unknown file type’
- Tooling mismatch: xobjdump errors or unexpected output
Fix steps
- Check the exact filename/extension: Parasolid binary is typically .x_b, not .xb.
- If it is truly .xb from an XMOS project, use XMOS XTC Tools (xobjdump) rather than CAD software.
OS-specific troubleshooting
What is a .XB file?
In the XMOS toolchain, xobjdump can create a new XE file with the suffix .xb, where ELF sectors are replaced with flat binary images and load addresses. Practically, this makes the file part of XMOS build/debug workflows rather than a standalone format meant for end-user apps.
Background
The .xb extension is ambiguous in the wild, but one documented and specific use is in XMOS XTC Tools: the xobjdump utility can emit a modified XE file using the .xb suffix. In that output, the program’s ELF sectors are transformed into flat binary images alongside load address information, which is useful in embedded workflows when you need a representation closer to what is loaded onto hardware.
Because this file is produced by a vendor tool and is tightly coupled to XMOS’s XE/ELF handling, most general-purpose applications will not recognize it. The most reliable approach is to use XMOS’s own tooling to inspect or convert it as needed.
A common point of confusion is with Parasolid “X_B” CAD files: Parasolid’s binary format is typically named X_B and commonly uses the extension .x_b (underscore). If your file came from CAD/CAE software, confirm whether it is actually .x_b rather than .xb before choosing tools.
Further reading
Authoritative resources for more details on the .XB format.
- XMOS XTC Tools Guide v15.3 (PDF)
- IANA Media Types registry (to verify if any MIME type exists)
- Shared MIME-info Database specification (how extension-to-MIME mappings are defined on Linux desktops)
- Parasolid (Wikipedia) — notes on .x_b as a binary Parasolid extension
- Spatial glossary: X_B file (Parasolid Binary File Format)
Common .XB issues
The file won’t open in CAD/3D software
.xb is easy to confuse with Parasolid binary files, which are commonly .x_b (with an underscore). XMOS .xb files are tooling outputs tied to XE/ELF handling and are not Parasolid CAD exchange files.
- Check the exact filename/extension: Parasolid binary is typically .x_b, not .xb.
- If it is truly .xb from an XMOS project, use XMOS XTC Tools (xobjdump) rather than CAD software.
Windows asks which app to use / ‘Unknown file type’
XMOS .xb outputs are not a common desktop file type and usually do not have system file associations.
- Install XMOS XTC Tools and use xobjdump from the command line to work with the file.
- If you just need to identify it, confirm it came from an XMOS build step that ran xobjdump to produce an .xb-suffixed XE output.
Tooling mismatch: xobjdump errors or unexpected output
The .xb-suffixed output is defined in XMOS tool documentation; using an incompatible tool version or expecting a different input/output type can lead to failures.
- Verify you are using the XMOS XTC Tools/xobjdump version documented for your project (the v15.3 docs describe the .xb output behavior).
- Recreate the .xb from the original XE using the documented xobjdump options so the file matches what downstream steps expect.
FAQ
Is a .xb file a Parasolid 3D model?
Usually no. Parasolid’s binary format is typically called X_B and commonly uses the extension .x_b (with an underscore). The .xb extension is documented in XMOS tooling as an xobjdump-generated XE-related output.
What program opens .xb files?
For the documented .xb usage, use XMOS XTC Tools—specifically xobjdump—to inspect or process the file.
Is there an official MIME type for .xb?
No specific .xb MIME type is confirmed by the provided sources. The authoritative place to check registered media types is the IANA Media Types registry.
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