A URL may only contain a limited set of characters, so spaces, accented letters, ampersands and slashes inside a value have to be percent encoded before they travel. This tool does that in both directions and lets you pick which of the two standard rules to apply. Component encoding escapes everything that is not safe inside a single value. Full URI encoding leaves the delimiters that give an address its structure alone, so a complete link stays clickable.
Picking the wrong one is the most common source of broken links. If you encode a whole URL with component rules the slashes and colon become %2F and %3A and the address stops working. If you encode a single search term with full URI rules an ampersand inside it survives and splits your query into two parameters. The parser panel below takes any URL, pulls the query string apart and shows each parameter with its value decoded, which makes tracking tags and redirects easy to read.
How to use the URL Encoder Decoder
- Choose Encode or Decode, then pick Component for a single value or Full URI for a whole address.
- Paste your URL or value into the input box and click Convert.
- Tick Treat + as a space if your data came from an HTML form, where spaces are written as plus signs.
- To inspect a link, paste it into the query string parser and click Parse parameters to see every name and decoded value.
Frequently asked questions
What is the difference between encodeURI and encodeURIComponent?
encodeURI is for a complete address and leaves the structural characters slash, colon, question mark, ampersand, equals, hash and plus untouched. encodeURIComponent is for one piece of a URL and escapes those characters too. Use component encoding for query values and path segments.
Why do I sometimes see %2520 in a URL?
That is a double encoded space. A space becomes %20, then the percent sign itself gets encoded again as %25, producing %2520. It usually means a value was encoded twice by two different layers. Decode the string twice to confirm, then remove the extra encoding step.
Should a space be a plus sign or %20?
Both appear in the wild. HTML form submissions use plus in the query string, which is the application/x-www-form-urlencoded rule. Percent 20 is correct everywhere else, including path segments where a plus is a literal plus. Use the checkbox to switch between the two.
What causes a malformed URI error?
Decoding fails when a percent sign is not followed by two hexadecimal digits, for example a literal percent in a discount code such as 50%off. It also fails on a percent sequence that is not valid UTF-8. Encode a literal percent sign as %25 before decoding.