Base64 Encode / Decode
Encode text to Base64 or decode Base64 strings back to plain text. Supports full Unicode characters.
How It Works
Base64 is a binary-to-text encoding scheme that represents binary data as a string of printable ASCII characters. It is widely used in web development to embed images in HTML or CSS, encode email attachments via MIME, and transmit data through URLs or APIs that only accept text.
The encoding process takes every three bytes of input and converts them into four Base64 characters chosen from the set A-Z, a-z, 0-9, + and /. If the input length is not a multiple of three, the output is padded with one or two = characters.
This tool fully supports Unicode text. When encoding, it first converts the string to UTF-8 bytes using encodeURIComponent and unescape, then applies the standard btoa function. Decoding reverses this process with atob, escape, and decodeURIComponent.
All encoding and decoding happens entirely in your browser using JavaScript. Your data is never sent to any server, ensuring complete privacy. The conversion runs live as you type, giving you instant results.