URL Encoder & Decoder

Percent-encode or decode URL components instantly

🔒 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 →

Use encodeURIComponent for query parameters and path segments (encodes / ? # &). Use encodeURI for entire URLs (preserves reserved characters).

使い方

  1. 1
    Paste text or URL

    Drop any string or URL into the input box.

  2. 2
    Pick encode or decode

    Use encodeURIComponent for query params or encodeURI for full URLs.

  3. 3
    Copy the result

    Copy the encoded or decoded output with one click.

URL Encoder & Decoder について

Free URL encoder and decoder. Convert plain text or query-string parameters to percent-encoded (RFC 3986) format, or decode existing URLs back to readable text. Handles Unicode, spaces, reserved characters - all in your browser. 712 Tools の URL Encoder & Decoder 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

What is the difference between encodeURI and encodeURIComponent?

encodeURI preserves reserved URL characters (/, ?, #, &) - use it on entire URLs. encodeURIComponent encodes those too - use it on individual query parameters or path segments.

Does it support Unicode?

Yes. Emoji and non-ASCII characters are UTF-8 encoded per RFC 3986 (e.g. é becomes %C3%A9).

Why do spaces become %20 instead of +?

%20 is the standard per RFC 3986. + is only valid inside application/x-www-form-urlencoded form data, not in real URLs.

Is my URL sent anywhere?

No. Encoding and decoding both use built-in browser APIs. Nothing leaves your device.

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