%20 in a URL

The percent-encoded space.

Short answer

%20 is the percent-encoded space character. A URL cannot contain a literal space, so a space is written as a percent sign followed by its byte value in hexadecimal, 20. In form-encoded query strings a space can also appear as a plus sign.

Character: space
Percent-encoded: %20
Byte value: 0x20 = 32
RFC 3986 class: unsafe
UTF-8 bytes: 1

Where you will see it

File names and paths with spaces: /reports/Q3%20summary.pdf.
Query values built with encodeURIComponent, Python's quote or Uri.EscapeDataString.
Links copied from a browser's address bar, which stores spaces as %20.

What goes wrong

%20 and + are not interchangeable everywhere. A plus means a space only in form-encoded data, such as HTML form submissions and URLSearchParams output. In a URL path, a plus is a literal plus sign, so a path must use %20.
Seeing %2520 means the % in %20 was encoded a second time. Decode once more to get the space, then fix the code that encodes an already-encoded value.

Decoded examples

Encoded	Decodes to	What it is	Open in the decoder
my%20file.pdf	my file.pdf	A file name containing a space.	Open in decoder
q=fish%20and%20chips	q=fish and chips	A query parameter with spaces in its value.	Open in decoder
a%2520b	a%20b	Double-encoded: one decode gives a%20b, a second gives a b.	Open in decoder

How each language encodes a space

Outputs below come from running each function, not from documentation. “Kept” means the function leaves the character as it is. Compare every character across every function.

Language	Function	Output for space
JavaScript	encodeURIComponent	%20
JavaScript	encodeURI	%20
JavaScript	URLSearchParams	+
JavaScript	escape (deprecated)	%20
Python	quote (default safe='/')	%20
Python	quote (safe='')	%20
Python	quote_plus	+
C#	Uri.EscapeDataString	%20
C#	WebUtility.UrlEncode	+
C#	HttpUtility.UrlEncode	+

Questions

Is %20 the same as a plus sign?

Only in form-encoded query strings, where a plus sign is read as a space. Everywhere else, including URL paths, a plus is a literal plus and a space must be %20. When unsure, use %20: it is valid in every part of a URL.

Why does my URL show %20 instead of spaces?

URLs may only contain a limited set of ASCII characters, and a space is not one of them. Browsers and libraries replace each space with %20 so the address stays unambiguous. Pasting the link into the URL decoder shows the original text.

Decode or encode your own text

Paste anything containing %20. It runs in your browser; nothing is uploaded.

URL Decoder URL Encoder

Related characters

%2B

plus sign

%2B is the percent-encoded plus sign (+).

%25

percent sign

%25 is the percent-encoded percent sign (%).

%3F

question mark

%3F is the percent-encoded question mark (?).

All percent-encoded characters · Full percent-encoding table · What is URL encoding?

Behaviour checked against RFC 3986, the WHATWG URL Standard and MDN. Updated November 4, 2026

URL Encoder

Percent-encode a value, a full URL or form data, with strict RFC 3986 and +/%20 options.

URL Parser

Split a URL into scheme, host, port, path, query and fragment, with checks for common problems.

Query String Parser

Edit query parameters as a table, rebuild the string, or export it as JSON.

Base64 Encode/Decode

Convert text to Base64 and back, including the URL-safe Base64URL alphabet.

HTML Encode/Decode

Escape text to HTML entities and decode entities back to text.

JWT Decoder

Read a JSON Web Token's header and payload and check its expiry.