How to Encode Spaces in URLs

Pattern

%20

or + specifically inside a query string

Explanation

A space is never valid literally inside a URL — %20 is the correct, universal way to represent one, and it works in every part of a URL: the path, the query string, and the fragment.

Query strings have one additional option: a literal + also means a space there, following the older application/x-www-form-urlencoded convention that URLSearchParams and most server frameworks still use. This only applies inside a query string — a + in a path segment means a literal plus sign, not a space, which is exactly why mixing the two up is such a common bug.

See URL Encoding Explained for the full mechanism behind both forms, or How to Encode Special Characters in URLs for a quick-reference table covering more than just spaces.

Valid examples

/files/my%20file.txt
A space in a path segment — always %20, never +.
?q=hello%20world
A space in a query value — %20 always works here too.
?q=hello+world
A space in a query value using the form-encoding convention — decodes the same as %20, but only inside a query string.
#section%20one
A space in a fragment — %20, the same as a path segment.

Invalid examples

/files/my file.txt
An unencoded literal space — invalid to construct programmatically, even though some browsers silently fix it on navigation.
/files/my+file.txt
Using + in a path segment — decodes to a literal plus sign, not a space. The +-for-space rule is query-string only.
/files/my_file.txt
Substituting an underscore or hyphen instead of encoding — changes the actual value rather than representing the original space.
?q=hello%2520world
Double-encoding — the % itself got encoded a second time, producing %2520 instead of %20.

Try it now

URL Encode

Percent-encode text or URLs, with component or full-URI mode.