URL Escape Online Encoder & Decoder

UrlEncode UrlDecode

What is URL Encoding

URL encoding, also known as percent-encoding, is a mechanism for converting characters into a format that can be safely transmitted inside a URL.

Purpose of Encoding

• Complying with the URL specification: URLs may only contain a specific character set: letters, digits and a few special characters (such as -_.~). Characters outside this set must be encoded before they can appear in a URL. For example, a space is not allowed literally in a URL and is encoded as %20.
• Preventing ambiguity: Some characters have special meanings in a URL, such as /, ? and &. Without encoding they can break URL parsing. For example, to pass a parameter value that itself contains a question mark ?, the question mark must be encoded, otherwise it would be mistaken for the query-string delimiter.

Encoding Rules

• For characters that require encoding, convert the ASCII value to hexadecimal and prefix it with a % sign. For example, the ASCII value of # is 35, which is 23 in hexadecimal, so # is encoded as %23.
• Reserved and unreserved characters: Reserved characters are those used to delimit different parts of a URL (such as /, ?, :, #, [, ], @, !, $, &, ', (, ), *, +, ,, ;, =) plus the character that controls encoding itself (%). When they are not used for their special purpose, they generally need to be encoded. Unreserved characters are letters, digits and -_.~; these can appear in a URL directly without encoding.

Use Cases

Passing URL parameters: When parameters are passed through a URL, values containing special or non-ASCII characters must be URL-encoded. For example, on a search page, if the keyword entered by the user contains spaces or other special characters, it must be encoded before being appended to the URL, as in https://www.example.com/search?q=hello%20world, where "hello world" becomes hello%20world after encoding.

Form submission: When data is submitted through an HTML form, the browser automatically URL-encodes field values containing special characters before sending them to the server. For example, in a login form, if the username contains special characters, the browser encodes it before including it in the request.

AJAX requests: When making AJAX requests in JavaScript, URLs or parameters containing special characters also need to be URL-encoded to ensure the server parses the request correctly.

Go Implementation

url.QueryEscape("https://www.cyeam.com")

Character	URL-Encoded	Description
Space	%20	One of the most common encodings on the web, replaces a space
Slash	%2F	Separates URL path segments (as in https%3A%2F%2Fexample.com )
Question mark	%3F	Marks the start of the query string (as in ?key=value )
Equals sign	%3D	Joins keys and values in query parameters (as in key%3Dvalue )
Ampersand	%26	Separates multiple query parameters (as in key1%3Dvalue1%26key2%3Dvalue2 )
Hash	%23	Used for URL fragments (as in #section )
Plus sign	%2B	Represents a space or a literal plus (common in form submissions)
Percent sign	%25	Escapes itself (because URL encoding starts with % )
Comma	%2C	Separates parameters or path parts (e.g. CSV download links)
Colon	%3A	Separates the URL scheme and port (as in https%3A// )
Semicolon	%3B	Used to separate parameters in some URL formats
Greater-than sign	%3E	Encoding of the > symbol
Less-than sign	%3C	Encoding of the < symbol
Exclamation mark	%21	Encoding of the ! symbol
Asterisk	%2A	Encoding of the * symbol
Single quote	%27	Encoding of the ' symbol
Double quote	%22	Encoding of the " symbol
Parentheses	%28 (left), %29 (right)	Encoding of the ( and ) symbols
Square brackets	%5B (left), %5D (right)	Encoding of the [ and ] symbols
Curly braces	%7B (left), %7D (right)	Encoding of the { and } symbols
Vertical bar	%7C	The `|` symbol
Tilde	%7E	Encoding of the ~ symbol
At sign	%40	Encoding of the @ symbol (common for email addresses in URLs)
Dollar sign	%24	Encoding of the $ symbol
Pound sign	%A3	Encoding of the £ symbol (may vary by charset)