URL Encoder / Decoder

Encode and decode URLs and URI components online

Input

Output

encodeURI vs encodeURIComponent:
encodeURI encodes a full URL but preserves : / ? # [ ] @ ! $ & ' ( ) * + , ; =
encodeURIComponent encodes everything except A-Z a-z 0-9 - _ . ~ — use this for query parameter values.

How URL Encoding Works

URL encoding (percent-encoding) replaces unsafe characters with a % followed by two hexadecimal digits representing the character's UTF-8 byte value.

Common Encodings

Space → %20 (or + in form data)
& → %26
= → %3D
? → %3F
# → %23

When to Use

Passing special characters in URL query parameters
Encoding form data before submission
Building API request URLs with dynamic values

Frequently Asked Questions

What is URL encoding?

URL encoding replaces unsafe ASCII characters with a '%' followed by two hex digits. For example, a space becomes %20. This ensures URLs are transmitted correctly.

What is the difference between encodeURI and encodeURIComponent?

encodeURI encodes a full URI but preserves characters like :, /, ?, #, &. encodeURIComponent encodes everything except letters, digits, and - _ . ~ making it ideal for query parameter values.

When should I use URL encoding?

Use URL encoding when passing special characters in query parameters, form data, or any text that will be part of a URL to prevent breaking the URL structure.

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