JSON Formatter & Minifier
Format, minify, and validate JSON data in your browser.
Input
Output
How to Use
Paste JSON into the text area and press "Format" to prettify or "Minify" to compress to a single line. An error message is displayed for invalid JSON.
How It Works
Uses the browser's built-in JSON.parse for parsing and JSON.stringify for reformatting with indentation. Data is never sent to a server.
よくある質問
大きなJSONファイルでも処理できますか？
JSONのバリデーション（文法チェック）はできますか？
入力データはサーバーに送信されますか？
スマートフォンでも使えますか？
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