Encode component vs encode full URL
Component encoding (encodeURIComponent) escapes everything except letters, digits and - _ . ! ~ * ' ( ). Use it for a single value such as a search term inside a query string. Full URL encoding (encodeURI) leaves characters like : / ? # & = alone so a complete address keeps working.
Why encode at all?
URLs may only contain a limited set of characters. Spaces, accented letters, emoji and reserved symbols are replaced by a percent sign and two hex digits, so a space becomes %20 and an ampersand inside a value becomes %26 - otherwise it would be read as the start of a new parameter.
Plus signs
In HTML form submissions a space is sometimes written as +. In the path part of a URL a plus is a literal plus. Tick the box above to decode form-style data.
Frequently asked questions
What does %20 mean?
It is a space character written in percent-encoding.
Why is decoding failing?
A % sign must be followed by two hex digits. A stray % (like "100%") is invalid until it is encoded as %25.
Is the query parser sending my URL anywhere?
No, everything is parsed locally.