Base45 Encoder / Decoder
Encode and decode Base45 (RFC 9285), the byte-packing encoding used in the EU Digital COVID Certificate and other compact QR-code payloads. Two bytes become three Base45 characters; a trailing byte becomes two. Runs locally in your browser.
Encode
Decode
Base45 (RFC 9285) uses the 45-character alphabet 0–9 A–Z ␣ $ % * + - . / :. Encoding walks the input bytes two at a time: each pair is treated as a big-endian 16-bit value and written as three Base45 digits, least-significant first; a final lone byte is written as two digits. Decoding reverses this — three chars → two bytes, a trailing two chars → one byte — and rejects inputs whose group values overflow (a 3-char group must be ≤ 65535, a 2-char group must be ≤ 255) or whose length leaves a lone trailing character. Input text is encoded as UTF-8; decoded bytes are shown as UTF-8 text plus a hex view. Pairs with the Base32, Base58, Base62 and Base64 encoders. Everything runs locally — nothing leaves your browser.