Paste a URL or text to encode or decode it — everything runs locally in your browser and nothing is uploaded.
Query parameter inspector
Paste a full URL to break it into editable parameters, then rebuild it.
Frequently asked questions
What's the difference between the two encode modes?
encodeURIComponent escapes all reserved characters (& ? = / etc.), for encoding a single value. encodeURI keeps URL-structure characters intact, for encoding a whole URL. The checkbox switches between them.
Why does decode turn + into a space?
In application/x-www-form-urlencoded data (query strings from forms), spaces are encoded as +. The decoder converts + back to a space so form values read correctly.
Can I edit query parameters?
Yes. Paste a full URL into the inspector and it breaks out each parameter into editable fields. Change, add or remove them and the rebuilt, correctly-encoded URL updates live.
Is anything sent to a server?
No. All encoding, decoding and URL parsing happens in your browser with native JavaScript. Nothing is transmitted.
Encode vs. encode-component
- Encode as component (encodeURIComponent) escapes everything that isn't safe inside a single query value — including
& ? = / :. Use it when you're building one parameter value. - Unchecked (encodeURI) preserves the URL structure characters, so it's for encoding a whole URL while keeping it a valid URL.
- Decoding also converts
+back to a space, matching how form data is typically encoded. - The parameter inspector splits a URL into editable key/value pairs and rebuilds a correctly-encoded URL as you edit — handy for tweaking tracking params or API queries.
About URL encoding and decoding
URLs can only contain a limited set of characters, so spaces, accents and symbols must be 'percent-encoded' — a space becomes %20, for example. This tool encodes text so it's safe to put in a URL, and decodes percent-encoded URLs back to readable text.
It runs in your browser; nothing is uploaded.
Common uses
- Building a query string with values that contain spaces or symbols.
- Decoding a long, cryptic URL to see what it actually says.
- Fixing a link that breaks because of an unencoded character.
- Preparing text for a URL parameter in code.
Use it carefully
Encode the individual values in a URL, not the whole URL at once — encoding the slashes and colons of a full address will break it. If you're not sure which part to encode, encode just the piece that goes after a = in the query string.
Understanding your results
Encoding replaces unsafe characters with percent codes: spaces become %20, an ampersand becomes %26, and so on. The result is safe to drop into a URL.
Decoding turns those codes back into the characters they represent, making a tangled link readable again.
When do I need to URL-encode something?
Whenever a value in a URL contains a space, an accent, or a symbol like & or ? that has special meaning.
Should I encode the whole URL?
No — encode only the values (usually the parts after = in the query string), or you'll break the address.
Is my text sent anywhere?
No. Encoding and decoding happen in your browser.
red & blue becomes red%20%26%20blue because & has a special meaning inside a query string. It does not protect or hide sensitive information; anyone with the encoded link can decode it back.
Why URLs need escaping
URLs use certain characters as structural separators. Percent-encoding provides a way to represent bytes that cannot safely appear literally in a particular URL component.
Why `%20` often means a space
Percent-encoding writes a byte as % followed by two hexadecimal digits. ASCII space is hexadecimal 20, producing %20 in a percent-encoded URL component.