URL encoding and decoding online. Convert special characters, Cyrillic, and spaces to URL-safe format
URL encoding replaces special characters with %XX sequences.
This is necessary for correctly passing parameters in URLs, working with APIs, and handling strings with Cyrillic characters.
The "Encode" button uses encodeURI (preserves URL structure), "encodeURIComponent" encodes all special characters including /, ? and &.
URL Encoding and Decoding Online
URL encoding (percent-encoding) represents special characters in URLs. Characters outside the allowed set (RFC 3986) are replaced with %XX, where XX is the hexadecimal UTF-8 byte value. This is necessary for correctly transmitting non-ASCII characters, spaces, and special symbols in browser address bars.
Why URL Encoding Is Needed
URLs can only contain ASCII characters. Non-Latin characters, spaces, and symbols like &, =, ? have special meaning and must be encoded for correct server interpretation.
Special Character Encoding Table
| Character | Code | Description |
|---|---|---|
| Space | %20 or + | In path — %20, in query — may be + |
| & | %26 | Query parameter separator |
| = | %3D | Key=value separator |
| ? | %3F | Query string start |
| # | %23 | Fragment (anchor) start |
encodeURI vs encodeURIComponent
| Function | Does NOT encode | Use for |
|---|---|---|
encodeURI() | : / ? # [ ] @ ! $ & ' ( ) * + , ; = | Full URLs |
encodeURIComponent() | - _ . ~ ! ' ( ) * | Individual parameters |
Frequently Asked Questions
Why do non-ASCII characters look like %XX in URLs?
Each non-ASCII character occupies 2–4 bytes in UTF-8, and each byte is encoded as %XX.
What is the difference between %20 and +?
RFC 3986 always encodes spaces as %20. The + for space is only used in application/x-www-form-urlencoded (HTML forms).
Is it safe to use?
Yes, all operations run in your browser. No data leaves your computer.
For HTML entity encoding use HTML Entities, for Base64 — Base64 encoder.
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