URL Encoder / Decoder

What is URL encoding?

URL encoding (also called percent-encoding) converts characters that are not allowed in a URL into a format that can be transmitted over the internet. Each unsafe character is replaced by a % sign followed by two hexadecimal digits representing its UTF-8 byte value.

For example, a space becomes %20, an ampersand becomes %26, and a hash sign becomes %23.

When to use it

• Embedding query-string values that may contain &, =, or +
• Passing URLs as parameters inside other URLs
• Encoding non-ASCII characters (e.g. Chinese, Arabic, emoji) in URLs
• Sanitising user input before appending to a URL
• Decoding percent-encoded strings received from a server or API

How this tool works

Encoding uses the browser's built-in encodeURIComponent(), which encodes all characters except A–Z a–z 0–9 - _ . ! ~ * ( ). Single quotes and double quotes are also encoded for maximum compatibility.

Decoding uses decodeURIComponent() after converting any + signs to spaces, supporting both application/x-www-form-urlencoded and standard percent-encoded strings. Everything runs entirely in your browser — no data is sent to a server.

Common encoded characters

• space → %20
• & → %26
• = → %3D
• + → %2B
• / → %2F
• ? → %3F
• # → %23
• @ → %40