URL Encoder/Decoder

URL encoding, also known as percent encoding, converts characters into a format that can be transmitted over the internet. Special characters, spaces, and non-ASCII characters are converted to percent signs followed by hexadecimal codes (like %20 for space). This is necessary because URLs can only contain certain safe characters.

Characters that need encoding include spaces, special characters like &, ?, #, =, +, %, and non-ASCII characters. Reserved characters used in URLs (like ? for query parameters, & for separating parameters, # for fragments) must be encoded when used as data rather than URL structure.

URL encoding uses percent signs and hexadecimal codes (%20 for space), while HTML encoding uses ampersand and semicolon (& for &). URL encoding is for URLs and query parameters, while HTML encoding is for HTML content to prevent XSS attacks and display special characters correctly.

Query parameters should have their keys and values encoded separately. For example, "search query=hello world&category=news" becomes "search%20query=hello%20world&category=news". The & and = characters that separate parameters should not be encoded as they're part of the URL structure.

Yes! The tool properly handles international characters (Unicode) by converting them to their UTF-8 byte sequences and then percent-encoding each byte. For example, "café" becomes "caf%C3%A9" where %C3%A9 represents the UTF-8 encoding of the é character.

Double-encoding will encode the percent signs themselves. For example, "%20" (encoded space) becomes "%2520". This can break URLs, so it's important to decode first if you're unsure whether a URL is already encoded, or check that your input isn't already encoded.

The hexadecimal digits in URL encoding are not case-sensitive - %2F and %2f both represent a forward slash. However, it's conventional to use uppercase letters A-F. The tool outputs uppercase hex digits following standard conventions.

Yes! This tool is perfect for encoding form data that will be sent in URLs (GET requests) or for preparing data for application/x-www-form-urlencoded POST requests. It properly handles the encoding needed for both URL query parameters and form data submission.