Base45 Encoder and Decoder

Encode binary data for restricted character sets

Base45 was designed for environments such as alphanumeric QR codes that cannot use the full Base64 character set efficiently. RFC 9285 groups two bytes into three Base45 characters and a final single byte into two. This tool applies that exact little-endian digit order to UTF-8 text and validates decoded groups before converting bytes back to readable text.

The two ASCII bytes in AB combine to decimal 16706 and encode as BB8. Decoding BB8 reconstructs the same bytes and returns AB. A three-character group may represent at most 65535, while a two-character tail may represent at most 255; values above those bounds are rejected instead of being silently truncated into incorrect data.

Check groups and byte ranges during decoding

Base45 is an encoding, not compression or encryption, so it can enlarge data and reveals its contents to anyone with a decoder. The page requires decoded bytes to be valid UTF-8. Processing remains in your browser. Keep spaces intact because the space character is part of the RFC alphabet, and do not automatically trim a value copied from a QR payload.