How this tool works
Apply component encoding to one parameter value or one path segment at a time. Form mode follows the query form convention in which plus represents a space and a literal plus must be encoded.
Encode reserved bytes as percent followed by two hexadecimal digits. Form mode also represents spaces with plus.A worked example
The component café & tea becomes caf%C3%A9%20%26%20tea.
Good to know
The tool processes one component or form value. Decode rejects malformed UTF-8 or incomplete percent sequences.
Reference: WHATWG URL Standard percent encoding (opens in a new tab) ↗
How the inputs affect the result
Keep delimiters such as the slash between path segments or ampersand between query fields outside the component you encode. Otherwise they become ordinary text bytes in the value.
The literal plus is encoded, while the intervening plus means space.
Where the calculation applies
The tool processes one component or form value. Decode rejects malformed UTF-8 or incomplete percent sequences.
For a related calculation, see the Base64 and Base64url UTF-8 encoder decoder.
Read more: WHATWG URL Standard percent encoding (opens in a new tab) ↗
A few questions, answered
How do I preserve a plus sign in a form value?
Encode the plus as %2B. An unescaped plus is read as a space when decoding form data.
What does the “Decode a form value” setting illustrate?
The literal plus is encoded, while the intervening plus means space.