Understanding URL Encoding and Decoding

What is URL Encoding?

URL encoding, also known as percent-encoding, is a mechanism that encodes information in a Uniform Resource Identifier (URI) by replacing certain characters with one or more character triplets that consist of the percent character % followed by two hexadecimal digits. These digits represent the numeric value of the replaced character.

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, URL encoding is necessary to convert these characters into a format that can be transmitted over the Internet.

What is URL Decoding?

URL decoding is the inverse process of URL encoding. It converts percent-encoded characters back to their original form, essential for correct data interpretation.

Common Use Cases

• Preparing data for HTTP GET parameters: Data included in URL parameters must be URL encoded.
• Embedding URLs within URLs: URL encoding prevents misinterpretation when a URL is included as part of another URL.