URL Encoder / Decoder

No. Encoding, decoding, and URL parsing all run in your browser using native JavaScript APIs. No data leaves your device.

encodeURIComponent encodes everything except letters, digits, and - _ . ! ~ * ' ( ). encodeURI additionally leaves : / ? # [ ] @ & = + $ , ; % intact — it is meant for full URLs where you want to preserve URL structure. Use encodeURIComponent for individual query values; use encodeURI when encoding a complete URL.

decodeURIComponent throws on malformed percent-sequences like a bare % or %xy where xy is not valid hex. The tool surfaces the browser's exact error so you can identify the offending character.