Encode text to Base64 or decode Base64 back to plain text.
Base64 is a binary-to-text encoding scheme that represents binary data as ASCII characters. It's commonly used to embed images in HTML/CSS, encode email attachments (MIME), transmit data in URLs, and store complex data in JSON or XML.
Base64 encoding takes groups of 3 bytes (24 bits) and converts them into 4 ASCII characters from a set of 64 characters (A-Z, a-z, 0-9, +, /). The encoded output is always ~33% larger than the original data.