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URL Encoder & Decoder

Encode URLs, query strings, and special characters—or decode percent-encoded values instantly.

RFC 3986 supportInstant validationNo data stored

URL or Plain Text

Paste or type the value to convert

55 bytes

Encoded Output

Converted result, ready to use

73 bytes
https%3A%2F%2Fexample.com%2Fsearch%3Fq%3Dhello%20world%26category%3Dtools

URL encoded successfully.

Conversion Ready

Technical Specs

Maximum Size
1 MB
Standards
RFC 3986 + Form
Validation
Strict percent sequences
Privacy
No database storage

Safe web values

Why encode URL values?

URLs reserve characters such as spaces, ampersands, hashes, and question marks for special purposes. Percent encoding preserves your actual data so browsers, servers, and APIs interpret it correctly.

What is URL Encoder & Decoder?

URL Encoder and Decoder converts text into percent-encoded bytes that can safely occupy a URL component and reverses valid encoded sequences back to readable text. Developers can distinguish RFC 3986 component encoding from form encoding, where spaces are commonly represented by plus signs.

How to use URL Encoder & Decoder

  1. 1.Select Encode or Decode and identify whether the value is a path component, query value, or form field.
  2. 2.Paste the source text and choose RFC 3986 or form-style processing.
  3. 3.Convert the value and review percent sequences, spaces, Unicode characters, and reserved delimiters.
  4. 4.Copy the result into the application and test the complete URL to detect double encoding.

Key features

  • ✓RFC 3986 mode encodes unsafe bytes without applying form-specific space rules.
  • ✓Form mode supports application/x-www-form-urlencoded plus-sign behavior.
  • ✓Strict decoding reports malformed or incomplete percent sequences.
  • ✓UTF-8 input is converted into the appropriate encoded byte representation.
  • ✓Swap and download controls support repeatable debugging workflows.

Common use cases

  • Encode a redirect parameter before adding it to a query string.
  • Decode a callback URL copied from an application log.
  • Prepare non-ASCII search text for an API request.
  • Compare `%20` and plus-sign handling in an HTML form integration.

Frequently asked questions

What is URL percent encoding?

It represents a byte as a percent sign followed by two hexadecimal digits so unsafe or reserved characters can travel in a URL component.

Should I use RFC 3986 or form encoding?

Use RFC 3986 for general URL components. Use form encoding when working with application/x-www-form-urlencoded query or form data.

Why does a decoded plus sign sometimes become a space?

Form encoding commonly uses plus for a space, while RFC 3986 treats a literal plus separately. Select the mode that matches the source.

What causes double URL encoding?

Encoding an already encoded percent sign turns it into `%25`, so `%20` may become `%2520`. Encode each value exactly once at the correct application boundary.

Can I encode an entire URL at once?

Usually individual components should be encoded separately so structural characters such as colon, slash, question mark, and ampersand keep their intended meaning.

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