URL Encoder
Encode and decode URL components.
LocalYour data is processed locally in your browser and is not uploaded to Alphzen.
Paste text to encode or decode.
How to use
- Paste the text or URL.
- Choose Component for query values, or URI if reserved characters such as : / should stay.
- Optionally encode spaces as + (common in application/x-www-form-urlencoded).
- Encode or Decode, then copy the result.
Features
- encodeURIComponent and encodeURI modes, matching JavaScript’s built-ins.
- Optional + instead of %20 when encoding components.
- Decode treats + as space unless you turn that off.
- Explains incomplete % sequences instead of throwing a raw URIError.
- Local processing only.
Examples
Ada Lovelace & Co
Ada%20Lovelace%20%26%20Co
FAQ
When should I use component vs URI?
Use component for a query parameter, path segment, or form field. Use URI when you have a full URL and only want to escape what encodeURI considers unsafe, leaving : / ? # in place.
Why did decode fail?
A % must be followed by two hexadecimal digits. A trailing % or %2 is invalid. Fix the source or encode the percent sign as %25.
Is this the same as HTML entities?
No. URLs use percent-encoding. HTML uses entities such as &. Use the HTML Entity tool for markup.
Related tools
About this tool
Percent-encoding is how spaces, ampersands, and non-ASCII characters enter a URL without breaking the parser. Alphzen uses the same rules as the JavaScript encodeURIComponent and encodeURI functions.
Form bodies often use + for space. That is not the same as a URL path. The option is there so you can match the context you are actually editing.
Decoding is strict. Invalid escape sequences are reported rather than silently truncated.