Input
Output

Percent-encoding replaces characters that have a reserved meaning in a URL — or that cannot appear in one at all — with a “%” followed by their byte value in hexadecimal. You need it when a query string carries spaces, Japanese text, or symbols such as & that would otherwise split the parameter.

How to use

  1. Paste the value you want to put into a URL.
  2. Characters outside the unreserved set are percent-encoded using their UTF-8 bytes.
  3. Copy the result into your query string or path segment.

FAQ

Are spaces encoded as %20 or as +?

As %20. The + form applies only to application/x-www-form-urlencoded form bodies, not to URLs in general.

Which characters are left alone?

The unreserved set: A–Z, a–z, 0–9 and - _ . ~ , along with ! * ' ( ) which are safe in practice. Everything else is encoded.

Why does one Japanese character become nine characters?

Encoding works per UTF-8 byte, and most Japanese characters are three bytes, so each one turns into three %XX groups.