JavaScript Formatter

JavaScriptコードの整形と圧縮。

入力

出力

Indent:

Beautify & Minify

Format JavaScript with proper indentation.

String Safe

Handles strings, comments, and template literals.

Copy Result

One-click copy to clipboard.

Client-side

All processing in your browser. No data uploaded.

JavaScript Formatterについて

The JavaScript & TypeScript Formatter is a free, browser-based tool that instantly beautifies or minifies your JavaScript and TypeScript code. Whether you received a minified bundle from a third-party library, wrote a quick script without caring about style, or need to reduce file size for production deployment, this formatter handles it all without requiring any installation or account. Beautifying adds consistent indentation to nested blocks, separates statements onto individual lines, and makes logic much easier to read and debug. Minifying strips whitespace, collapses line breaks, and removes comments to produce the smallest possible output — ideal for reducing page load times. The formatter correctly handles single-quoted, double-quoted, and template-literal strings so their contents are never accidentally modified, and it skips over both single-line (//) and block (/* */) comments. All processing happens entirely in your browser, meaning your proprietary code never leaves your machine. Adjust the indentation size between 2 and 4 spaces to match your team's coding style guide.

JavaScript Formatterの使い方

Paste your JavaScript or TypeScript code into the left input panel.
Choose your preferred indentation size (2 or 4 spaces) using the dropdown at the bottom.
Click "Beautify" to format the code with proper indentation and line breaks, or click "Minify" to compress it.
Review the formatted output in the right panel.
Click "Copy" to copy the result to your clipboard and paste it wherever you need it.

よくある質問

Does this formatter support TypeScript?

Yes. Because TypeScript is a superset of JavaScript syntax, the formatter handles TypeScript code correctly — including type annotations, generics, and interfaces — using the same parsing logic.

Is my code sent to a server?

No. All formatting and minification runs entirely in your browser using JavaScript. Your code never leaves your device and is not stored anywhere.

Why does the beautified output look slightly different from Prettier?

This tool uses a lightweight, dependency-free formatter focused on indentation and line breaks. For strict style enforcement (semicolons, quotes, trailing commas), use Prettier in your local development environment.

Can I use the minified output in production?

Yes, but for serious production use it is recommended to also run a proper bundler like esbuild or Terser, which perform dead-code elimination and other advanced optimizations on top of whitespace removal.

What is the difference between beautify and minify?

Beautify adds whitespace and indentation to make code human-readable. Minify removes all unnecessary whitespace and comments to make files as small as possible for faster delivery to end users.

JavaScript Formatterの完全ガイド：無料オンラインツール

ブラウザ完結で安全・高速なJavaScript Formatter。開発者やクリエイターの作業を効率化

JavaScriptコードの整形と圧縮。を瞬時に実現する無料ツールです。面倒なソフトのインストールは不要で、安全にブラウザ上で処理できます。

JavaScript Formatterが選ばれる理由

高速処理: ミリ秒単位で即時実行。
プライバシー保護: データは端末外に送信されません。
完全無料: 登録不要で制限なく利用可能。

簡単な3つの利用手順

JavaScript Formatterのページを開きます。
データを入力または貼り付けます。
結果を確認してコピーまたは保存します。

機能比較

項目	Metoolzy JavaScript Formatter	他社オンラインツール	専用ソフト
料金	完全無料	制限あり	有料ライセンス
セキュリティ	完全ローカル処理	サーバー送信あり	ローカル処理