CheckNet.

Encode and decode

Everything runs in this browser; nothing you type here is sent anywhere.

Encoding is not encryption

Base64, URL and hex only change how data is written so it survives places where not every character is allowed; anyone can turn them back without a key. Never “hide” a password or secret with Base64.

Punycode turns Persian and other non-Latin domain names into Latin letters, because DNS only knows Latin ones. A JWT is a token sites use for logins; its contents are just Base64 that anyone can read, but its signature stops tampering.