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URL Encoder/Decoder | Online URL Converter (UTF-8)

Professional online URL Encoder/Decoder. Supports UTF-8, provides encodeURIComponent and encodeURI modes, perfectly handles special characters and parameters. Essential for web development.

URL Converter

Encoding Mode

How to Use URL Encoder/Decoder

  • **Select Action**: Click 'Encode' to convert special characters to percent coordinates, or 'Decode' to restore the original string.
  • **Understand Modes**: 'encodeURIComponent' encodes almost all non-alphanumeric characters, best for query parameter values; 'encodeURI' preserves URL syntax characters (like : / ? #), best for full URLs.
  • **Input Content**: Paste the text or URL you want to process in the left input box. Supports strings of any length.
  • **View Result**: The converted result will appear instantly in the right output box.
  • **Copy Result**: Click the copy button above the output box to copy the result to your clipboard.
  • **Swap & Clear**: Use the Swap button to quickly exchange input and output for continuous operations; use Clear to reset everything.
  • **Note**: When decoding, ensure the input format is correct. Invalid percent-encoding sequences (like %G0) may cause errors.

URL Encoding Deep Dive

What is URL Encoding (Percent-encoding)?

URL encoding, officially known as percent-encoding, is a mechanism for encoding information in a Uniform Resource Identifier (URI). Characters that are not allowed in a URL (like spaces or non-ASCII characters) must be translated into a format that can be transmitted over the Internet. It replaces unsafe ASCII characters with a '%' followed by two hexadecimal digits.

Why is URL Encoding Necessary?

URLs can only be sent over the Internet using the ASCII character-set. Since URLs often contain characters outside the ASCII set, the URL has to be converted into a valid ASCII format. URL encoding replaces unsafe ASCII characters with a '%' followed by two hexadecimal digits. For example, a space is replaced by '%20'. This ensures no ambiguity in parsing the URL.

UTF-8 and URL Encoding

Modern web standards recommend using UTF-8 as the basis for URL encoding. In UTF-8, a non-ASCII character is converted into one or more bytes. Each of these bytes is then percent-encoded. For example, the character 'É' in UTF-8 is 0xC3 0x89, so it becomes '%C3%89'. This allows URLs to support characters from virtually all human languages.

Common Character Encodings

Space → %20 (or + in some contexts); Slash / → %2F; Colon : → %3A; Question mark ? → %3F; Equals = → %3D; Ampersand & → %26; Hash # → %23. Note that letters (A-Z, a-z), numbers (0-9), and a few symbols (- _ . ! ~ * ' ( )) are unreserved and do not need to be encoded.

Key Features

  • **Dual Mode Support**: Provides both component and URI encoding modes to suit different needs.
  • **UTF-8 Ready**: Fully supports multi-byte characters, ensuring correct encoding for Chinese, Emoji, and other non-Latin scripts.
  • **Instant Processing**: Powered by client-side JavaScript, conversion happens instantly without sending data to a server.
  • **Privacy Focused**: Your data never leaves your browser, ensuring maximum privacy and security.
  • **Large Text Support**: Optimized performance allows for processing very large text blocks without lag.

Common Applications

  • **Web Development**: Essential for encoding query parameters in AJAX requests to prevent malformed URLs.
  • **Data Scraping**: Used to properly encode search terms or parameters when building URLs for web scrapers.
  • **API Testing**: Critical for sending data containing special characters (like / or &) in RESTful API paths or queries.
  • **File Downloads**: Ensures filenames with special characters or non-English text are correctly handled by browsers.
  • **Debugging**: Quickly decoding opaque URL strings in browser address bars to understand their contents.