URL Encode / Decode

URL Encoder / Decoder

Paste a URL or query string below. Choose Encode to percent-encode special characters, or Decode to convert %XX sequences back to readable text. Three encoding modes are available to suit different use cases.

Percent Encoding Reference

Common characters and their percent-encoded equivalents. Click any row to append that character to the input.

What is URL Encoding?

URL encoding (also called percent encoding) converts characters that are not allowed or have special meaning in a URL into a % followed by two hexadecimal digits representing the character's UTF-8 byte value. For example, a space becomes %20, the & character becomes %26, and the = sign becomes %3D. This ensures that URLs remain valid and unambiguous regardless of the characters in query strings or path segments.

Encoding Modes Explained

• encodeURIComponent — Encodes everything except letters, digits, and - _ . ! ~ * ' ( ). Use this for individual query parameter values. It encodes &, =, +, /, ?, and #, which is correct when they appear inside a value rather than as URL structure delimiters.
• encodeURI — Encodes everything except characters that are legal in a complete URI, preserving : / ? # [ ] @ ! $ & ' ( ) * + , ; =. Use this to encode a full URL without breaking its structure.
• Form Encoding (application/x-www-form-urlencoded) — Same as encodeURIComponent but replaces spaces with + instead of %20. This is used when submitting HTML form data via POST or GET.

How to Use the URL Encoder / Decoder

1. Choose Encode or Decode mode.
2. Select the appropriate Encoding Mode for your use case.
3. Paste your URL, query string, or plain text into the input box and click Encode / Decode.
4. View the output — encoded characters are highlighted in purple in the Encoded Characters panel.
5. If the input is a valid URL, a URL Structure Breakdown shows each component (protocol, host, path, query, fragment) and a Query Parameters table lists each key-value pair decoded.
6. Click Use as Input to swap the output back for round-trip testing.

Key Features

• 3 encoding modes: encodeURIComponent, encodeURI, and Form Encoding (x-www-form-urlencoded).
• Encoded character highlighting: Percent-encoded sequences shown in purple against unencoded text.
• URL structure breakdown: Automatically parses valid URLs into protocol, host, pathname, query, and fragment components.
• Query parameter table: Lists every key=value pair in the query string with decoded values.
• Live mode: Optional real-time encoding as you type.
• Percent encoding reference: Clickable reference chart for common characters.
• 100% browser-based: No data is sent to any server.

Common Use Cases

• API development: Encode query parameter values before appending them to endpoint URLs to prevent broken requests.
• Form submissions: Understand how browsers encode form data before sending it to a server.
• Debugging: Decode a URL you received to read the actual query parameter values.
• SEO and marketing: Decode campaign tracking URLs (UTM parameters) to read their values clearly.
• Security: Detect URL-encoded payloads used in injection attacks such as %3Cscript%3E → <script>.