Base45 Encoder/Decoder

Encode and decode Base45 as defined by RFC 9285, used in EU COVID QR codes.

Your files stay on this device

Files are processed in your browser, never uploaded. The site downloads code and assets to run the tools. No accounts or trackers.

Use Download to save this tool as one HTML file for offline use.

input

output

— output appears here —

About this tool

Convert text to and from RFC 9285 Base45 over UTF-8 bytes, entirely in your browser.

Where is Base45 used?

It encodes binary data into the QR-friendly alphanumeric set, notably for the EU Digital COVID Certificate.

How does the encoding work?

Bytes are taken in pairs and written as three Base45 characters; a lone trailing byte becomes two characters.