Regex Tester & Debugger

Test JavaScript regular expressions with live matches

🔒 100% ブラウザ内🆓 ずっと無料⚡ サインアップ不要
注意: 下記のツールインターフェースは現時点で英語のみに対応しています。UI の翻訳は順次進めています。 このツールを英語で見る →
Flags
0 matches

使い方

  1. 1
    Enter your pattern

    Type or paste your regex in the pattern box. Pick the flags you need (g, i, m, s, u).

  2. 2
    Add test text

    Paste the string you want to test against. Matches update live.

  3. 3
    Inspect matches

    See highlighted matches, capture groups, and total match count in real time.

Regex Tester & Debugger について

Free online regex tester for JavaScript regular expressions. See matches highlighted live as you type, view capture groups, test flags (g, i, m, s, u, y), and get match counts. Runs entirely in your browser - no signup, no ads inside the tool. 712 Tools の Regex Tester & Debugger はモダンな JavaScript API を使って完全にブラウザ内で動作します - サーバーがあなたのデータを見ることは一切ありません。つまり、即時の結果、完全なプライバシー、アップロード制限なしです。

デバッグ、簡単な確認、あるいは本番のインシデント対応まで - このツールは何度でも無料で使えます。ウォーターマークなし、サインアップなし、ツール内広告なし。

よくある質問

Which regex flavor is this?

JavaScript (ECMAScript) - the same regex engine that runs in your browser and Node.js.

Does it support named groups?

Yes. Named capture groups like (?<year>\d{4}) are shown alongside numbered groups in the results panel.

Is my pattern or text uploaded?

No. Everything runs in your browser via the native RegExp engine.

Why is my pattern hanging?

You may have hit catastrophic backtracking - a common issue with nested quantifiers like (a+)+. Simplify the pattern.

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