Number of CPUs.
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> Number of CPUs.
To use as a general utility, install the CLI package globally
``bash`
npm install -g @stdlib/os-num-cpus-cli
`text
Usage: num-cpus [options]
Options:
-h, --help Print this message.
-V, --version Print the package version.
`
`bash`
$ num-cpus
- [@stdlib/os-num-cpus][@stdlib/os-num-cpus]: number of CPUs.
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
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---
See [LICENSE][stdlib-license].
Copyright © 2016-2026. The Stdlib [Authors][stdlib-authors].
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[npm-url]: https://npmjs.org/package/@stdlib/os-num-cpus-cli
[test-image]: https://github.com/stdlib-js/os-num-cpus/actions/workflows/test.yml/badge.svg?branch=v0.2.3
[test-url]: https://github.com/stdlib-js/os-num-cpus/actions/workflows/test.yml?query=branch:v0.2.3
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/os-num-cpus/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/os-num-cpus?branch=main
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[chat-url]: https://stdlib.zulipchat.com
[stdlib]: https://github.com/stdlib-js/stdlib
[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors
[cli-section]: https://github.com/stdlib-js/os-num-cpus#cli
[cli-url]: https://github.com/stdlib-js/os-num-cpus/tree/cli
[@stdlib/os-num-cpus]: https://www.npmjs.com/package/@stdlib/os-num-cpus
[umd]: https://github.com/umdjs/umd
[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules
[deno-url]: https://github.com/stdlib-js/os-num-cpus/tree/deno
[deno-readme]: https://github.com/stdlib-js/os-num-cpus/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/os-num-cpus/tree/umd
[umd-readme]: https://github.com/stdlib-js/os-num-cpus/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/os-num-cpus/tree/esm
[esm-readme]: https://github.com/stdlib-js/os-num-cpus/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/os-num-cpus/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/os-num-cpus/main/LICENSE
[node-os]: https://nodejs.org/api/os.html#os_os_cpus
[hardware-concurrency]: https://developer.mozilla.org/en-US/docs/Web/API/NavigatorConcurrentHardware/hardwareConcurrency