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Percent-encoding - Glossary | MDN 1/3 https://developer.mozilla.org/en-US/docs/Glossary/Percent-encoding reference web, html, css, javascript, documentation 2026-05-05T05:40:13.513580+00:00 kb-cron

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  1. Glossary
  2. Percent-encoding

Percent-encoding

Percent-encoding is a mechanism to encode 8-bit characters that have specific meaning in the context of URLs. It is sometimes called URL encoding. The encoding consists of a substitution: A '%' followed by the hexadecimal representation of the ASCII value of the replaced character. Special characters needing encoding are: ':', '/', '?', '#', '[', ']', '@', '!', '$', '&', "'", '(', ')', '*', '+', ',', ';', '=', as well as '%' itself. Other characters don't need to be encoded, though they could.

Character Encoding
':' %3A
'/' %2F
'?' %3F
'#' %23
'[' %5B
']' %5D
'@' %40
'!' %21
'$' %24
'&' %26
"'" %27
'(' %28
')' %29
'*' %2A
'+' %2B
',' %2C
';' %3B
'=' %3D
'%' %25
' ' %20 or +
Depending on the context, the character ' ' is translated to a '+' (like in the percent-encoding version used in an application/x-www-form-urlencoded message), or in '%20' like on URLs.

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