URL Encoder / Decoder
Encode special characters in URLs for safe transmission, or decode percent-encoded strings back to readable text.
What Is URL Encoding?
URL encoding (percent-encoding) converts characters that are not permitted in a URL into a safe format. A URL can only contain letters, digits, and a few unreserved symbols. Every other character — including spaces, non-ASCII letters, and characters with special meaning in URL structure like ampersand, equals sign, and question mark — must be represented as a percent sign followed by two hexadecimal digits. A space becomes %20, an ampersand becomes %26.
Some characters are reserved because they serve structural roles in a URL. The slash separates path segments. The question mark begins the query string. The ampersand separates query parameters. The equals sign separates keys from values. If any of these characters appear as literal data values in a URL rather than as structural separators, they must be encoded so the URL parser does not misinterpret them.
When to Encode and Decode URLs
URL encoding is required any time text is inserted into a URL as a value. Search queries, return URLs, file paths, usernames, and any other text passed as a query parameter must be properly encoded. Without encoding, an ampersand in a parameter value would be interpreted as a separator, and the URL would be parsed incorrectly. In JavaScript, the correct function for encoding individual parameter values is encodeURIComponent().
Decoding is equally important: when your application receives URL-encoded data from a form submission, API request, or webhook, you must decode it to recover the original value. URL encoding also appears in deep links for mobile applications, redirect URLs in authentication flows, permalink generation for blog posts, and API request construction where parameters contain arbitrary user-supplied text.
How to Use URL Encoder / Decoder
- 1
Select Encode or Decode mode using the toggle.
- 2
Paste your URL or encoded string into the Input field.
- 3
The result appears in the Output panel automatically.
- 4
Click Copy to copy the result to your clipboard.
Frequently Asked Questions
What is URL encoding?
URL encoding (percent-encoding) replaces special characters with a % followed by two hex digits. For example, a space becomes %20. This is required to safely include characters in URLs.
When should I encode a URL?
Encode URLs when passing values in query strings, form submissions, or API requests. Characters like spaces, &, =, and # must be encoded to avoid breaking the URL structure.
What is the difference between encodeURI and encodeURIComponent?
encodeURI encodes a full URL and leaves characters like / and ? intact. encodeURIComponent encodes a URL component (like a query value) and also encodes those characters. Our tool uses encodeURIComponent.