🌐 URL Encoder Decoder

📚 Understanding URL Encoding

What is URL Encoding?

URL encoding (also known as percent encoding) is a method for converting special characters into a format that can be safely transmitted over the internet. URLs have a limited character set - they can only contain letters, digits, and certain special characters (- _ . ~). Any other character must be encoded. URL encoding replaces unsafe characters with a % followed by two hexadecimal digits representing the character's ASCII value.

Why URL Encoding is Necessary

URLs have special meanings for certain characters. For example, ? separates the domain from query parameters, & separates parameters, = assigns values, and # indicates a fragment. Spaces cannot appear in URLs at all. When you need to include these special characters as data rather than URL syntax, they must be encoded to avoid ambiguity and broken links.

URL Encoding Examples

Space: " " encodes to "%20" or "+"
Question Mark: "?" encodes to "%3F"
Ampersand: "&" encodes to "%26"
Equals: "=" encodes to "%3D"
Hash: "#" encodes to "%23"
Percent: "%" encodes to "%25"
Forward Slash: "/" encodes to "%2F"

Common URL Encoding Characters

Reserved characters in URLs that often need encoding: ! # $ & ' ( ) * + , / : ; = ? @ [ ]
Unreserved characters that don't need encoding: - _ . ~ and alphanumeric characters (A-Z, a-z, 0-9)

Real-World URL Encoding Applications

Search Queries: When you search Google, your query is URL encoded in the search parameter. "hello world" becomes "hello%20world" or "hello+world"

Form Data: When HTML forms are submitted using GET method, form data is URL encoded in the query string

API Requests: API parameters often contain special characters that must be encoded before transmission

File Names in URLs: Files with spaces or special characters in their names must be encoded to create valid URLs

URL vs Query String Encoding

URL Path Encoding: Encodes the path portion of URLs. Forward slashes (/) are usually NOT encoded as they're used to separate path segments
Query String Encoding: Encodes query parameters. Uses application/x-www-form-urlencoded format where spaces are + and & separates parameters

Frequently Asked Questions

Q: What's the difference between %20 and +? A: Both represent a space in URLs, but %20 is standard URL encoding while + is used in query strings (application/x-www-form-urlencoded). This tool uses %20

Q: Do I need to encode already encoded URLs? A: No, encoding already encoded data causes double encoding. %20 would become %2520, breaking the URL

Q: Why encode if modern browsers handle it automatically? A: Browsers often handle it automatically, but for APIs, parameters, and data transmission, you may need manual encoding for reliability