js-beautify CLI

Command-line interface for beautifying JavaScript files with js-beautify.

Synopsis

js-beautify [options] <file ...>

When installed globally (npm install -g js-beautify), the js-beautify executable is available on your PATH. Beautified output is written to stdout by default.

Pass - as a filename to read from stdin. When no files are provided and no stdin pipe is detected, the CLI prints an error and usage information.

Options

I/O options

Flag	Long form	Description
-f	--file	Input file(s). Pass - for stdin.
-r	--replace	Write output in-place, overwriting the input file.
-o	--outfile	Write output to a specific file instead of stdout.
	--config	Path to a JSON config file.
	--type	Select beautifier type: js, css, or html. Does not filter input files — only selects which beautifier to run. Default: js.
-q	--quiet	Suppress logging to stdout.
-h	--help	Show help and exit.
-v	--version	Show the version number and exit.

Indentation options

Flag	Long form	Default	Description
-s	--indent-size	4	Number of spaces per indentation level.
-c	--indent-char	" "	Character used for indentation.
-t	--indent-with-tabs	false	Indent with tabs, overrides -s and -c.
-l	--indent-level	0	Initial indentation level.
	--indent-empty-lines	false	Keep indentation on empty lines.
	--editorconfig	false	Use EditorConfig to set up options from .editorconfig.

Output formatting

Flag	Long form	Default	Description
-e	--eol	first newline in file, else \n	Line terminator character(s).
-n	--end-with-newline	false	End output with a newline.
-p	--preserve-newlines	true	Preserve existing line breaks. Use --no-preserve-newlines to disable.
-m	--max-preserve-newlines	10	Maximum blank lines to preserve in one chunk.
-w	--wrap-line-length	0	Wrap lines exceeding N characters. 0 disables wrapping.
-b	--brace-style	collapse	Brace style: collapse, expand, end-expand, none. Append ,preserve-inline to keep single-line blocks.
-C	--comma-first	false	Place commas at the start of new lines instead of the end.
-O	--operator-position	before-newline	Operator position on wrapped lines: before-newline, after-newline, preserve-newline.
	--templating	auto	Templating languages to recognize: auto, none, django, erb, handlebars, php, smarty, angular.

Space options

Flag	Long form	Default	Description
-P	--space-in-paren	false	Add padding spaces inside parentheses: f( a, b ).
-Q	--space-in-empty-paren	false	Add a space inside empty parentheses: f( ).
-j	--jslint-happy	false	Enable JSLint-stricter mode. Implies --space-after-anon-function.
-a	--space-after-anon-function	false	Add a space before anonymous function parens: function ().
	--space-after-named-function	false	Add a space before named function parens: function example ().

Method chaining

Flag	Long form	Default	Description
-u	--unindent-chained-methods	false	Do not indent chained method calls.
-B	--break-chained-methods	false	Break chained method calls onto separate lines.

Miscellaneous

Flag	Long form	Default	Description
-k	--keep-array-indentation	false	Preserve original array indentation.
-x	--unescape-strings	false	Decode printable characters encoded in \xNN notation.
-X	--e4x	false	Pass E4X XML literals through untouched.
	--good-stuff	—	Enables --keep-array-indentation and --jslint-happy together.

Examples

# Beautify from stdin to stdout (pipe to - filename)
echo 'function foo(){return 42;}' | js-beautify -

# Beautify a file, output to stdout
js-beautify app.js

# Beautify multiple files to stdout
js-beautify src/*.js

# Replace files in-place
js-beautify --replace src/main.js src/utils.js

# Write beautified output to a new file
js-beautify -o dist/formatted.js src/main.js

# Use 2-space indentation and end with a newline
js-beautify -s 2 -n app.js

# Indent with tabs, expand braces
js-beautify --indent-with-tabs --brace-style expand app.js

# Use a config file
js-beautify --config .jsbeautifyrc app.js

# Pipe from another tool
cat bundle.min.js | js-beautify - -s 2 > bundle.formatted.js

You can also use js-beautify --css or js-beautify --html as an alternative to the css-beautify and html-beautify commands. The --type flag selects the beautifier without filtering input files.

Configuration loading

The CLI resolves options from the following sources in priority order (highest to lowest):

1. CLI flags passed directly
2. jsbeautify_-prefixed environment variables
3. A JSON config file specified via --config
4. A .jsbeautifyrc JSON file found at or above the current working directory

Option names in .jsbeautifyrc use underscores instead of dashes, matching the library API names.