ONNX (Open Neural Network Exchange)
ONNX (Open Neural Network Exchange) is a framework maintained by ONNX project (hosted by the LF AI & Data Foundation)634, version 1.23.1, released Sep 29, 2026. Its source code is public1 under the Apache License 2.021.
ONNX is an open format for representing machine learning models, covering both deep learning and traditional ML. It defines an extensible computation graph model, built-in operators, and standard data types, with a current focus on inference. Facebook and Microsoft started the ONNX community in 2017, and LF AI announced it as a graduate-level project in November 2019.17
- Website: Website (external site: onnx.ai)
- Repository: GitHub repository (external site: github.com)
- Documentation: Python package documentation (external site: onnx.ai)
- Documentation: Open governance (external site: github.com)
- License: License (Apache 2.0) (external site: raw.githubusercontent.com)
- Release notes: PyPI package (external site: pypi.org)
Availability and license
Overall availability
Documented as available to the general public. Access conditions and license terms may still apply.12
Availability is separate from permission: read the license before using or redistributing.
Apache License 2.0 (external site: raw.githubusercontent.com)21
Plain-language guide to the Apache License 2.0
Source files carry the SPDX identifier Apache-2.0 with copyright attributed to the ONNX Project Contributors. The README points to the Linux Foundation's trademark usage rules for the ONNX mark.1
Component reuse rights
- weights
- Unknown — no complete fact-level rights review
- code
- Unknown — no complete fact-level rights review
- data
- Unknown — no complete fact-level rights review
- documentation
- Unknown — no complete fact-level rights review
No complete system-rights review is recorded for this release.
Public materials checklist
| Item | Status | Notes and evidence |
|---|---|---|
| Source codeIs the source code publicly readable? | Public | Developed in the public onnx/onnx GitHub repository.1 |
| DocumentationIs user documentation published? | Public | The repository links the IR specification, operator documentation, versioning principles, and Python API documentation.1 |
| InstallationAre installation instructions or packages publicly available? | Public | Installable from PyPI with pip install onnx; weekly builds are published as onnx-weekly.14 |
| Supported platformsAre supported operating systems or hardware documented? | Public | Version 1.23.1 requires Python 3.10 or later and ships wheels for Linux (x86_64 and aarch64), macOS (universal2), and Windows (x86, x64, and ARM64), plus a WebAssembly (Emscripten) wheel and a source distribution.45 |
| Release statusAre versioned releases published? | Public | Version 1.23.1 was released on PyPI on September 29, 2026.4 |
What it is useful for
Exchanging trained models between frameworks, tools, and hardware runtimes; the repository also provides a Python package with shape and type inference, opset version conversion, and a reference implementation.1
Organization context
U.S. eligibility
Eligible · basis: U.S.-governed project
ONNX is a hosted project of the LF AI & Data Foundation, a directed fund of The Linux Foundation; its PyPI contact list is on the LF AI & Data mailing-list domain and its README points to Linux Foundation trademark rules. The Linux Foundation is a 501(c)(6) nonprofit whose legal postal address is in San Francisco, California. Under the project's open governance, a five-member Steering Committee elected by community vote sets project direction, governance policy, and releases, with no more than one representative from any single member company; Special Interest Groups are responsible for specific parts of the project.68419103
Sources
This listing is not an endorsement, a safety assessment, or a federal approval.
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Cite this page
APA style
USASI. (2026, September 29). ONNX (Open Neural Network Exchange). United States of America Superintelligence. https://unitedstatesofamericasuperintelligence.com/open/onnx/
BibTeX
@misc{usasi_onnx,
author = {{USASI}},
title = {ONNX (Open Neural Network Exchange)},
year = {2026},
month = sep,
howpublished = {\url{https://unitedstatesofamericasuperintelligence.com/open/onnx/}},
note = {United States of America Superintelligence. Last updated 2026-09-29}
}The date is when this page was last updated. Add the date you read it if your style needs one.
For maintainers: a “Listed in USASI” badge
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