HTML Formatter

HTMLコードの整形と圧縮。

入力

出力

Indent:

Beautify & Minify

Auto-indent HTML or compress to single line.

Configurable

2 or 4 space indentation.

Copy Result

One-click copy to clipboard.

Client-side

All processing in your browser. No data uploaded.

HTML Formatterについて

The HTML Formatter is a free, in-browser tool that instantly beautifies or minifies HTML markup. Poorly indented HTML — whether generated by a CMS, exported from a design tool, or copy-pasted from a webpage — can be extremely difficult to read and maintain. The beautifier walks your document's tag structure and adds correct, consistent indentation so each nested element is visually offset from its parent, making the document hierarchy immediately clear. Void elements like <br>, <img>, <input>, and <meta> are handled automatically and never given a closing tag or incremented indent level. The minifier does the opposite: it collapses all whitespace between tags and trims excess spaces, producing a compact single-line output that loads faster in browsers. Choosing between 2-space and 4-space indentation lets you match your team's coding standards. Because the entire process runs in your browser, your HTML source code — which may include private API responses, internal application markup, or sensitive form structures — is never transmitted to any external server.

HTML Formatterの使い方

Paste your HTML markup into the left input panel.
Select the indentation size (2 or 4 spaces) from the dropdown at the bottom.
Click "Beautify" to add indentation and structure, or "Minify" to compress the HTML into one line.
Inspect the formatted output in the right panel.
Click "Copy" to copy the result to your clipboard, ready to paste into your project.

よくある質問

Does this tool handle void/self-closing HTML elements correctly?

Yes. Elements like <br>, <img>, <input>, <hr>, <meta>, and <link> are recognized as void elements and are never given a closing indent or expected closing tag.

Can I format HTML fragments, or does it need to be a full document?

You can format any HTML — full documents with <!DOCTYPE>, partial fragments, or even individual component templates. The tool works on whatever you paste in.

Is this safe for HTML containing sensitive data?

Yes. The formatter runs entirely in your browser. Your HTML is never sent to a server or stored anywhere outside your device.

Will minification break inline scripts or styles?

Inline <script> and <style> blocks may have their internal whitespace collapsed. For robust production minification with script-aware parsing, use a dedicated build tool like HTMLMinifier-terser.

What is the benefit of minifying HTML?

Minified HTML reduces the number of bytes the browser must download, which speeds up page load times — especially on slow connections. It also makes it slightly harder for competitors to read your source markup.

HTML 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HTML Formatter。開発者やクリエイターの作業を効率化

HTML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。

HTML 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

HTML 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 HTML 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