URL Encode / Decode
Percent-encode or decode text for use in URLs.
Results appear as you type
Everything runs locally in your browser — your input never leaves this page.
About the URL Encode / Decode
URL Encode / Decode percent-encodes text so it can be safely placed in a URL, or decodes percent-encoded strings back into readable characters. It correctly handles reserved characters such as spaces, ampersands and question marks that would otherwise break a query string. The tool works fully client-side, so your input stays private in your browser.
How to use
- Paste the text or URL component you want to convert.
- Select encode to percent-encode it, or decode to reverse it.
- View the converted string immediately.
- Copy the result into your link, API request or query parameter.
Percent-encoding differs by position in the URL
There is no single correct percent-encoding of a string, because what counts as a reserved character depends on where in the URL it sits. A `/` is structural in a path and must be encoded if it is part of a segment's value, but it is perfectly legal unescaped inside a query string. A `?` starts the query, so it must be encoded anywhere before that point. This is why JavaScript ships two functions: `encodeURI` preserves the characters that build a URL's structure, while `encodeURIComponent` escapes them because it assumes you are encoding one value to drop into that structure.
The space character is the classic ambiguity. In a path it becomes `%20`. In an `application/x-www-form-urlencoded` query string — the format HTML forms submit — it becomes `+`, and a literal plus must then be written `%2B`. Decoding a query string with a path decoder turns every `+` into a space, which quietly corrupts base64 values passed as parameters.
Encoding twice is the failure you will actually hit in production. `%` is itself a character that needs encoding, so a string run through an encoder twice turns `%20` into `%2520`. It usually surfaces as a redirect chain where each hop adds a layer, and the symptom is a literal `%2520` visible in the address bar.
Frequently asked questions
- What is the difference between encoding a full URL and a component?
- Encoding a whole URL preserves structural characters like slashes and colons, while encoding a single component (such as a query value) escapes them too. Use component encoding for individual parameter values.
- Why do spaces sometimes become %20 and other times a plus sign?
- In the path and standard percent-encoding a space is %20, while in the query string of HTML form submissions a space is often encoded as +. Both decode back to a space.
- Does this tool send my data anywhere?
- No. Encoding and decoding run entirely in your browser, so your text is never transmitted to a server.