URL Encoder Decoder

Encode or decode URL strings for safe web transmission.

Guides & Reference

How It Works

Encodes special characters using percent encoding: replaces unsafe characters with % followed by two-digit hex code. Spaces become %20.

Formula

Percent-encoding RFC 3986

Quick Reference

Common calculations — results you can verify instantly.

Space character

ASCII 32

%20

Ampersand &

ASCII 38

%26

Hash #

ASCII 35

%23

Forward slash /

Path separator

%2F in query only

Tips & Shortcuts

Use encodeURIComponent for query string values.

Use encodeURI for full URLs preserving : / ? and other URL characters.

Common Mistakes

Double encoding already-encoded URL

Encoding %20 again produces %2520. Check if already encoded first.

Using URL encoding for form data

HTML forms use + for spaces not %20.

Frequently Asked Questions

Spaces, special chars (&, =, ?, #, %, +), and non-ASCII all need encoding.

%20 is standard percent-encoding. + for space used only in form data (application/x-www-form-urlencoded).

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