Convert a string to lowercase.
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> Convert a string to lowercase.
``bash`
npm install @stdlib/string-lowercase
`javascript`
var lowercase = require( '@stdlib/string-lowercase' );
#### lowercase( str )
Converts a string to lowercase.
`javascript`
var str = lowercase( 'bEEp' );
// returns 'beep'
`javascript
var lowercase = require( '@stdlib/string-lowercase' );
var str = lowercase( 'Beep' );
// returns 'beep'
str = lowercase( 'BeEp' );
// returns 'beep'
str = lowercase( 'Beep BOOP' );
// returns 'beep boop'
str = lowercase( '$_Beep_BoOp_$' );
// returns '$_beep_boop_$'
str = lowercase( '' );
// returns ''
`
- [@stdlib/string-lowercase-cli][@stdlib/string-lowercase-cli]: CLI package for use as a command-line utility.
- [@stdlib/string-uncapitalize][@stdlib/string/uncapitalize]: uncapitalize the first character of a string.
- [@stdlib/string-uppercase][@stdlib/string/uppercase]: convert a string to uppercase.
*
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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].
[@stdlib/string-lowercase-cli]: https://www.npmjs.com/package/@stdlib/string-lowercase-cli
[npm-image]: http://img.shields.io/npm/v/@stdlib/string-lowercase.svg
[npm-url]: https://npmjs.org/package/@stdlib/string-lowercase
[test-image]: https://github.com/stdlib-js/string-lowercase/actions/workflows/test.yml/badge.svg?branch=v0.3.1
[test-url]: https://github.com/stdlib-js/string-lowercase/actions/workflows/test.yml?query=branch:v0.3.1
[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/string-lowercase/main.svg
[coverage-url]: https://codecov.io/github/stdlib-js/string-lowercase?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/string-lowercase#cli
[cli-url]: https://github.com/stdlib-js/string-lowercase/tree/cli
[@stdlib/string-lowercase]: https://github.com/stdlib-js/string-lowercase/tree/main
[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/string-lowercase/tree/deno
[deno-readme]: https://github.com/stdlib-js/string-lowercase/blob/deno/README.md
[umd-url]: https://github.com/stdlib-js/string-lowercase/tree/umd
[umd-readme]: https://github.com/stdlib-js/string-lowercase/blob/umd/README.md
[esm-url]: https://github.com/stdlib-js/string-lowercase/tree/esm
[esm-readme]: https://github.com/stdlib-js/string-lowercase/blob/esm/README.md
[branches-url]: https://github.com/stdlib-js/string-lowercase/blob/main/branches.md
[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/string-lowercase/main/LICENSE
[standard-streams]: https://en.wikipedia.org/wiki/Standard_streams
[@stdlib/string/uncapitalize]: https://www.npmjs.com/package/@stdlib/string-uncapitalize
[@stdlib/string/uppercase]: https://www.npmjs.com/package/@stdlib/string-uppercase