The URL Encoder/Decoder tool converts special characters to percent-encoded format for safe URL transmission. Whether you're encoding Chinese characters, handling special symbols, or decoding garbled URLs, this tool provides instant bidirectional conversion.
What is URL Encoding?
URL encoding (percent-encoding) converts characters that cannot appear directly in URLs into %XX format. URLs can only contain ASCII characters, with some reserved for special purposes. Any other characters must be encoded - each byte is converted to a percent sign followed by two hexadecimal digits.
Normal Mode vs Full Encode
- Normal mode (encodeURIComponent): Encodes non-ASCII characters and special symbols, but preserves URL structural characters like colon (:), slash (/), question mark (?), and hash (#). Suitable for encoding URL parameter values.
- Full encode mode: Encodes all non-alphanumeric characters including URL structural characters. Useful when the entire string must be safely transmitted, or when structural characters should be treated as literal characters.
Common Use Cases
Search Query Parameters: Chinese keywords in search URLs need encoding. Form Submissions: Special characters in form data need encoding before URL transmission. API Calls: Non-ASCII characters in API request URLs require encoding. File Links: URLs containing spaces or special characters in filenames need encoding.
FAQ
Q: Why are Chinese characters encoded as multiple %XX sequences?
A: Chinese characters are encoded using UTF-8, which represents each Chinese character with 3 bytes. Each byte is converted to %XX format, so one Chinese character becomes three percent-encoded sequences like %E4%B8%AD.
Q: What's the difference between encodeURI and encodeURIComponent?
A: encodeURI encodes a complete URL, preserving structural characters like ://?#. encodeURIComponent encodes a single component (like parameter values), also encoding structural characters. Use encodeURI for whole URLs, encodeURIComponent for individual parameters.
Q: Why do spaces sometimes become + and sometimes %20?
A: In application/x-www-form-urlencoded encoding (HTML form default), spaces are replaced with +. In standard URL encoding, spaces become %20. When decoding, both need to be correctly identified and restored to spaces.