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URL Encoder/Decoder

Encode and decode URL strings to ensure proper formatting and security

What is URL Encoding?

URL encoding (also known as percent encoding) is a mechanism for encoding information in a Uniform Resource Identifier (URI). It converts special characters and spaces into a format that can be safely transmitted over the internet. This is essential because URLs can only contain a limited set of ASCII characters.

Our free URL encoder/decoder tool allows you to encode special characters in URLs or decode encoded URLs back to their original form. This is crucial for web development, API integration, and ensuring proper data transmission.

Why Use URL Encoding?

  • Special Characters: Encode characters like spaces, &, =, # that have special meaning in URLs
  • International Characters: Encode non-ASCII characters (Unicode) for safe transmission
  • Query Parameters: Properly encode values in URL query strings
  • API Integration: Encode data for REST API requests and responses
  • Security: Prevent URL injection attacks and ensure data integrity

Key Features:

  • Bidirectional: Encode URLs or decode encoded URLs
  • Auto-Update: Real-time encoding/decoding as you type
  • Examples: Built-in examples for common encoding scenarios
  • Copy & Share: Easy export options for encoded/decoded URLs
  • Privacy-Focused: All processing happens client-side in your browser

Input

Output

URL Encoding Examples

hello world
Use
→ hello%20world
Spaces become %20
price=$100&discount=50%
Use
→ price%3D%24100%26discount%3D50%25
Special characters encoded
query=search term&sort=date
Use
→ query%3Dsearch%20term%26sort%3Ddate
Query parameters
email=user@example.com
Use
→ email%3Duser%40example.com
Email in URL parameters

Complete Guide to URL Encoding

URL encoding (also known as percent-encoding) converts characters into a format that can be safely transmitted over the internet. It ensures that URLs remain valid and secure by encoding special characters that have reserved meanings in URLs or cannot be represented directly in ASCII.

The encoding process converts each special character into a percent sign (%) followed by two hexadecimal digits representing the character's ASCII code. For example, a space character (ASCII 32) becomes %20, and an ampersand (&, ASCII 38) becomes %26.

Why URL Encoding is Important:

  • Security: Prevents URL injection attacks and ensures data integrity
  • Compatibility: Ensures URLs work across different systems and browsers
  • Reliability: Prevents broken links from special characters
  • Standards Compliance: Follows RFC 3986 URL encoding standards
  • International Support: Enables encoding of Unicode and non-ASCII characters

Commonly Encoded Characters:

Space
→ %20
&
→ %26
=
→ %3D
@
→ %40

When to Use URL Encoding:

  • Query parameters in URLs
  • Form data submission
  • API requests with special characters
  • URLs containing spaces or non-ASCII characters
  • Data being passed in HTTP headers

Technical Details:

// JavaScript functions used:
encodeURIComponent(string) - Encodes a URI component
decodeURIComponent(string) - Decodes a URI component

// Example:
encodeURIComponent('hello world') = 'hello%20world'
decodeURIComponent('hello%20world') = 'hello world'

Best Practices:

  • Always encode user input before including it in URLs
  • Use encodeURIComponent() for query parameters
  • Use encodeURI() for complete URLs (preserves ://, etc.)
  • Decode URLs before displaying to users
  • Validate decoded input for security