URL Encoder / Decoder
Encode and decode URLs with percent-encoding Free, browser-based, no sign-up required.
What is URL Encoder / Decoder?
URL encoding (also known as percent-encoding) is a mechanism for converting characters that are not allowed in a URL into a safe representation using percent signs followed by two hexadecimal digits. For example, a space becomes %20 and an ampersand becomes %26. This is essential when passing user input, query parameters, or special characters in URLs, form submissions, and API requests. This tool supports both component-level encoding (encodeURIComponent) and full URI encoding (encodeURI) to handle different use cases.
How to Use
Choose Encode or Decode mode. For encoding, paste your text and select a mode — encodeURIComponent (recommended for query parameters) or encodeURI (for full URLs). The output updates in real-time as you type. Click Copy to copy the result to your clipboard.
How It Works
The encoder uses the browser's built-in encodeURIComponent() or encodeURI() functions. encodeURIComponent encodes all characters except A-Z, a-z, 0-9, and - _ . ~ making it safe for query parameter values. encodeURI leaves URL-structural characters like :, /, ?, and # intact. The decoder uses decodeURIComponent() to reverse percent-encoded sequences back to readable text.
Common Use Cases
- Encoding query string parameters before appending to URLs
- Decoding URLs from server logs or analytics reports
- Preparing form data for application/x-www-form-urlencoded submissions
- Safely embedding user-generated content in URL paths
- Debugging percent-encoded API request parameters
- Converting non-ASCII characters (Unicode) for URL-safe transmission
Frequently Asked Questions
What is the difference between encodeURI and encodeURIComponent?▼
encodeURI encodes a complete URI but leaves structural characters like ://?#[]@ intact. encodeURIComponent encodes everything except A-Z, a-z, 0-9, and -_.~ — use it for individual query parameter values to ensure special characters like & and = are properly escaped.
When should I use URL encoding?▼
Always encode user input or dynamic values before placing them in URLs. This prevents broken URLs from spaces or special characters, avoids injection attacks, and ensures non-ASCII characters (like Chinese or Arabic text) are transmitted correctly.
Does this tool send my data to a server?▼
No. All encoding and decoding is performed entirely in your browser using built-in JavaScript functions. Your data never leaves your device.
Why does my URL have + instead of %20 for spaces?▼
The + sign for spaces comes from the application/x-www-form-urlencoded format used in HTML form submissions. Standard percent-encoding uses %20. This tool uses standard percent-encoding (%20). If you need + for spaces, replace %20 with + after encoding.