UF2 File Viewer

UF2 (USB Flashing Format) is a binary file format designed for flashing microcontrollers over USB mass storage (a USB drive). This online viewer decodes a .uf2 firmware file into its 512-byte blocks and shows every header field (magic numbers, flags, target address, payload size and family ID) alongside the raw bytes.

Everything runs in your browser: files are read locally and never uploaded to a server. Open a .uf2 file to inspect its blocks, header fields and content.