Encoding & Crypto

Encoding & Crypto brings together 9 focused tools for working with encoded data, text transformations, and lightweight ciphers. Every tool runs entirely in your browser -- nothing you paste is ever transmitted, logged, or stored. The JWT Encoder performs HMAC signing using the browser's WebCrypto API; your secret never leaves your device, though the tool includes a prominent security warning that only test secrets should be used. The tools fall into three groups. Encode/decode pairs (Base64 Encode & Decode, URL Encode & Decode, HTML Entity Encode & Decode) cover the most common encoding formats every developer encounters: Base64 for embedding binary data in text protocols, URL percent-encoding for safe query strings, and HTML entities for displaying code snippets without breaking page layout. Byte-level converters (Binary to Text, Hex to Text) show the exact underlying bytes of any text -- how 'A' is 01000001 or 0x61, and how a four-byte emoji maps to f0 9f 98 8a in hex -- giving you a direct window into UTF-8 encoding. Ciphers and signals (Morse Code Converter, ROT13 Cipher, Caesar Cipher, JWT Encoder) cover the boundary between encoding and cryptography, from recreational (Morse, ROT13, Caesar) to practical (JWT signing for development and testing). A note on security: none of these tools provides real encryption. ROT13 and Caesar are classical ciphers breakable in milliseconds. The JWT Encoder should only be used with test secrets in development. For actual confidentiality, use a properly implemented library with AES-GCM or ChaCha20-Poly1305, not these encoding tools.