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URL Encode/Decode

URL-encode and decode text instantly. Supports component and full URI modes.

100% Private — Your files never leave your device.

All processing happens in your browser. Nothing is uploaded to any server.

Encodes everything — use for query parameters and values

Common URL Encodings Reference
Space→%20
!→%21
#→%23
$→%24
&→%26
+→%2B
/→%2F
:→%3A
=→%3D
?→%3F
@→%40
%→%25
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How it works

What Is URL Encoding?

URL encoding (percent-encoding) is a mechanism for encoding characters that aren’t allowed in URLs. It replaces unsafe characters with a % sign followed by two hexadecimal digits representing the character’s byte value.

Why It Exists

URLs can only contain a limited set of characters from the US-ASCII character set. The RFC 3986 specification defines which characters are allowed:

  • Unreserved characters (always safe): A-Z a-z 0-9 - _ . ~
  • Reserved characters (have special URL meaning): : / ? # [ ] @ ! $ & ' ( ) * + , ; =
  • Everything else must be percent-encoded

Component vs Full URI Mode

FeatureComponent ModeFull URI Mode
FunctionencodeURIComponent()encodeURI()
EncodesEverything except A-Z a-z 0-9 - _ . ! ~ * ' ( )Only spaces and non-ASCII characters
PreservesNothing else: / ? # @ ! $ & ' ( ) * + , ; =
Use forQuery parameter valuesComplete URLs with minor issues

When to Use Each

Component mode — Use when encoding a single value that will be placed into a URL:

// Encoding a search query for a URL parameter
?search=hello%20world%26more  ← correct (& is encoded)

Full URI mode — Use when you have a complete URL that just needs spaces or accented characters fixed:

https://example.com/my page → https://example.com/my%20page  ← correct (structure preserved)

Common Encoded Characters

CharacterEncodedDescription
(space)%20Most common encoding
!%21Exclamation mark
#%23Hash/fragment
$%24Dollar sign
&%26Ampersand (query separator)
+%2BPlus sign
/%2FForward slash
:%3AColon
=%3DEquals sign
?%3FQuestion mark
@%40At sign

Privacy

All encoding and decoding happens in your browser using JavaScript’s native encodeURIComponent() and decodeURIComponent() functions. No data is sent to any server.

Real-World Examples

1

Encoding a search query parameter

Mode: Encode (Component) Text: best café in São Paulo

A developer needs to pass a user's search query as a URL parameter. The text 'best café in São Paulo' contains accented characters that aren't safe in URLs. Component encoding produces 'best%20caf%C3%A9%20in%20S%C3%A3o%20Paulo', which can be safely appended to a URL like '?q=best%20caf%C3%A9%20in%20S%C3%A3o%20Paulo'.

2

Decoding a URL from analytics

Mode: Decode Text: https%3A%2F%2Fexample.com%2Fpath%3Fq%3Dhello%20world%26lang%3Den

A marketing analyst receives a fully-encoded URL from their analytics platform. Decoding reveals the original URL: 'https://example.com/path?q=hello world&lang=en'. This makes it easy to understand which pages users are visiting without mentally parsing percent-encoded characters.

3

Encoding a full URL with spaces

Mode: Encode (Full URI) Text: https://example.com/my page?name=John Doe

A developer has a URL with spaces that needs to be valid. Using Full URI mode preserves the URL structure (://?=) while encoding only the spaces: 'https://example.com/my%20page?name=John%20Doe'. Unlike Component mode, this preserves the URL's structural characters.

Frequently Asked Questions

What is URL encoding?
URL encoding (also called percent-encoding) converts characters into a format that can be safely transmitted in a URL. Characters that aren't allowed in URLs (spaces, special characters, non-ASCII) are replaced with a percent sign followed by their hexadecimal value. For example, a space becomes %20, an ampersand becomes %26, and a forward slash becomes %2F.
What is the difference between Component and Full URI encoding?
Component encoding (encodeURIComponent) encodes everything except A-Z, a-z, 0-9, and - _ . ! ~ * ' ( ). Use it for query parameter values. Full URI encoding (encodeURI) preserves URL structure characters like : / ? # [ ] @ ! $ & ' ( ) * + , ; = so the URL remains navigable. Use it when encoding a complete URL that just has spaces or non-ASCII characters.
Why do I see %20 instead of + for spaces?
Both %20 and + represent spaces in URLs, but in different contexts. %20 is the standard percent-encoding for spaces (RFC 3986) and works everywhere. The + sign for spaces is only valid in the query string portion of a URL (application/x-www-form-urlencoded format, used by HTML forms). Our tool uses %20 because it's universally correct.
Which characters need to be URL-encoded?
Any character not in the 'unreserved' set must be encoded: unreserved characters are A-Z, a-z, 0-9, hyphen (-), underscore (_), period (.), and tilde (~). Reserved characters like : / ? # @ have special meaning in URLs and must be encoded when used as data (not as delimiters). All non-ASCII characters (accented letters, Chinese characters, emoji) must always be encoded.
Can I URL-encode binary data?
Technically yes — every byte can be percent-encoded — but it's extremely inefficient. A 1KB binary file would become roughly 3KB of percent-encoded text. For binary data in URLs, use Base64 encoding first (our Base64 tool), then URL-encode the Base64 string if needed. This is how data URIs and many APIs handle binary payloads.
Is URL encoding the same as HTML encoding?
No. URL encoding uses percent signs (%20, %3C) to make characters safe for URLs. HTML encoding uses ampersand-based entities (&, <, ') to make characters safe for HTML documents. They solve different problems: URL encoding ensures valid URLs, HTML encoding prevents XSS attacks and display issues in web pages.

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