Free URL Encoding Reserved Characters

The Need for URL Encoding

URLs can only be sent over the Internet using the ASCII character-set. Because URLs often contain characters outside the ASCII set, or contain characters that have special meaning (like &, =, and ?), the URL has to be encoded into a valid ASCII format.

Reserved vs. Unreserved

Characters are divided into "reserved" (those with syntactic meaning in the URL, like / or #) and "unreserved" (alphanumerics). URL encoding (percent-encoding) replaces unsafe or reserved characters with a % followed by two hexadecimal digits representing that character's ASCII value (e.g., Space becomes %20).

Local Encoding Security

When passing highly sensitive session IDs or tokens via URL parameters, developers utilize offline encoders. This ensures the raw strings are converted to URL-safe formats locally before being pasted into potentially monitored network environments.