Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to text, UTF-8 safe.
About the Base64 Encoder / Decoder
Base64 encodes binary or text data into an ASCII-only string, which is why it shows up everywhere — data URIs, email attachments, JWT tokens, API payloads and config files. The AlarmDaddy Base64 Encoder / Decoder converts text to and from Base64 entirely in your browser, with full UTF-8 support so emoji and accented characters survive the round trip.
Paste text to encode it, or paste a Base64 string to decode it back. The tool handles Unicode correctly (many naive Base64 tools break on non-ASCII text). Use it to inspect a token, build a data URI, or debug an API request.
How to use this calculator
- 1Choose Encode or Decode.
- 2Paste your text or Base64 string.
- 3Read the converted output.
- 4Copy the result with one click.
The formula
Input bytes are grouped in threes (24 bits) and split into four 6-bit values, each mapped to one of 64 printable characters (A–Z, a–z, 0–9, + and /). Padding with = makes the length a multiple of four. Decoding reverses the mapping.