URL Encoder / Decoder

URLコンポーネントのエンコード・デコード。
結果

Encode & Decode

encodeURIComponent and encodeURI modes.

Real-time

Results update as you type.

Copy Result

One-click copy to clipboard.

Client-side

All processing in your browser. No data uploaded.

URL Encoder / Decoderについて

URL encoding, also called percent-encoding, converts characters that are not allowed or have special meaning in URLs into a safe format. Each unsafe character is replaced by a percent sign followed by its two-digit hexadecimal code point — for example, a space becomes %20 and an ampersand becomes %26. This tool supports two standard JavaScript functions: encodeURIComponent encodes everything except letters, digits, and the characters - _ . ! ~ * ' ( ), making it ideal for encoding individual query parameter values. encodeURI encodes a full URL and preserves characters like : / ? # & = that have structural meaning in a URL. Proper URL encoding is essential for building web applications, constructing API request URLs, handling form submissions, and ensuring links work correctly across browsers and operating systems. Decoding lets you inspect encoded URLs and query strings in a human-readable form. This tool processes everything client-side so your data stays private.

URL Encoder / Decoderの使い方

  1. Choose "Encode" to percent-encode text or "Decode" to convert encoded strings back to plain text.
  2. Select the encoding scope: use "encodeURIComponent" for a single value (e.g., a query param), or "encodeURI" for a full URL.
  3. Type or paste your text into the input field.
  4. The encoded or decoded result appears instantly in the output field.
  5. Click "Copy" to copy the result to your clipboard.

よくある質問

What is the difference between encodeURIComponent and encodeURI?

encodeURIComponent encodes almost everything except basic alphanumeric characters, making it suitable for encoding individual query parameter values. encodeURI preserves characters that are structurally part of a URL (like /, ?, #, &) so it is meant for encoding complete URLs.

Why does a space become %20 and not +?

%20 is the standard percent-encoding for a space. The + notation for spaces is specific to the application/x-www-form-urlencoded format used in HTML form submissions, not in general URLs.

When would I need to URL-encode a string?

Whenever you embed a value inside a URL — such as a search query, a file path, or a user-provided parameter — you should URL-encode it to prevent special characters from breaking the URL structure or being misinterpreted by the server.

Can I URL-decode multiple parameters at once?

Yes — paste the full query string (e.g., name=John%20Doe&city=S%C3%A3o+Paulo) and switch to Decode with encodeURIComponent mode to see the decoded result. Each parameter will be decoded inline.

Is this tool safe for sensitive data?

All processing happens in your browser with no server communication, so your data remains private. That said, URL encoding is not encryption — encoded values can be decoded by anyone who sees them.

URL Encoder / Decoder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URL Encoder / Decoder。開発者やクリエイターの作業を効率化

URLコンポーネントのエンコード・デコード。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。

URL Encoder / Decoder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

  1. URL Encoder / Decoderのページを開きます。
  2. データを入力または貼り付けます。
  3. 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 URL Encoder / Decoder 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

主な活用シーン

  • エンジニアの開発・デバッグ効率化
  • Web制作者の日常作業
  • データ変換・最適化

よくある質問 (FAQ)

入力したデータは保存されますか？

いいえ、すべてブラウザ内で処理され保存されません。