What's the difference between encodeURI and encodeURIComponent?

encodeURI encodes a complete URL, preserving characters that have special meaning in URLs (like : / ? # @). encodeURIComponent encodes individual components more aggressively, converting all special characters including those used as URL delimiters.

Why do spaces become %20 or + in URLs?

Spaces can be encoded as %20 (standard percent-encoding) or + (form data encoding). The + encoding is commonly used in query strings from HTML forms, while %20 is the standard URL encoding for spaces.

Is my data sent to a server?

No. All encoding and decoding happens 100% in your browser using JavaScript. Your data never leaves your device.

Processed locally. No data reaches our servers.

URL Encoder & Decoder

Encode special characters for safe URL transmission or decode percent-encoded strings back to readable text.

Method: Auto-process

Input (Plain Text) 0 chars

Output (Encoded)

0 chars

Quick Examples:

URL Components Parser

Use Cases

Encode query parameters for API requests
Decode URLs from logs or analytics tools
Handle special characters in filenames
Build redirect URLs with parameters
Debug URL encoding issues in web apps

Common Encodings

Space%20 or +

&%26

=%3D

?%3F

/%2F

#%23

@%40

:%3A

Encoding Methods

encodeURIComponent

Encodes everything except: A-Z a-z 0-9 - _ . ! ~ * ' ( )

encodeURI

Preserves URL structure chars: ; / ? : @ & = + $ , #

Form Encoding

Like encodeURIComponent but uses + for spaces

Frequently Asked Questions

What is URL encoding?

URL encoding, also called percent-encoding, converts characters that aren't allowed in URLs or have special meaning into a format that can be safely transmitted. Each unsafe character is replaced with a % followed by two hexadecimal digits representing its ASCII value. For example, a space becomes %20.

When should I use encodeURI vs encodeURIComponent?

Use encodeURI when encoding a complete URL - it preserves characters like : / ? # that are valid URL delimiters. Use encodeURIComponent when encoding individual components like query parameter values, as it encodes all special characters including URL delimiters.

Why do spaces become + or %20?

Both are valid representations of a space in URLs. The %20 encoding is the standard percent-encoding. The + symbol is used in the application/x-www-form-urlencoded format, which is what HTML forms use when submitting data. Most servers accept both, but %20 is more universally compatible.

How do I encode Unicode characters?

Unicode characters are first converted to UTF-8 bytes, then each byte is percent-encoded. For example, the emoji 🚀 becomes %F0%9F%9A%80. JavaScript's encodeURIComponent handles this automatically, making it safe to include any Unicode text in URLs.

Is my data secure?

Yes, completely. All encoding and decoding happens entirely in your browser using JavaScript. Your data never leaves your device and is not sent to any server. You can verify this by checking the Network tab in your browser's developer tools.