What This Tool Does (And Why the Output Matches Prettier Exactly)
This code beautifier online is a straightforward wrapper around Prettier itself, not a custom from-scratch formatter, so beautify javascript code you paste here comes back exactly as Prettier would format it locally with the same options, no approximation, no drift. That distinction matters because many generic online code beautifier tools implement their own formatting logic, which can disagree with Prettier's actual output in small but real ways, spacing, line breaks, quote style choices, that end up mattering once the formatted code lands in a project that expects Prettier's conventions.
How to Beautify Code With This Tool
Paste your code into the input field, choose the language, JavaScript, TypeScript, JSX, TSX, CSS, SCSS, Less, HTML, Markdown, GraphQL, YAML, JSON, or XML, adjust the formatting options if you want something other than the defaults, and the formatted output appears with the time it took to format. There is nothing to install, so you can beautify code online, or format javascript online specifically, in the time it takes to paste and copy. Copy the result directly into your project.
Formatting Options Explained
Tab width controls how many spaces represent one indent level. Print width sets the line length Prettier tries to wrap at before breaking onto a new line. Single quote switches string literals between single and double quotes where the language allows it. Semicolons toggles whether statements end with a semicolon in JavaScript and TypeScript. Trailing comma controls whether a trailing comma is added to the last item in a multi-line list, none, es5-safe, or all, matching Prettier's own trailingComma setting exactly.
Which Languages Are Supported
JavaScript, JSX, TypeScript, and TSX are all formatted through Prettier's Babel and TypeScript parsers. CSS, SCSS, and Less each get their own dedicated parser, as do HTML, Markdown, GraphQL, YAML, and JSON. XML support comes from the official @prettier/plugin-xml package, since XML formatting isn't part of Prettier's core. This makes it a genuine typescript formatter online and javascript formatter online in one tool, alongside solid support for the CSS family and structured-data formats.
Common Uses for a Code Beautifier
Cleaning up a minified or hand-mangled file you need to actually read, standardizing style on a snippet before pasting it into a pull request or a Stack Overflow answer, formatting code shared in Slack or a support ticket back into something readable, and getting Prettier-quality output without setting up a local Prettier install are all common reasons to use a code formatting tool like this one.