Computes the CRC32 checksum using the standard IEEE 802.3 polynomial 0xEDB88320, the same variant used by zip, gzip, PNG and Ethernet. It builds a 256-entry lookup table once, then processes the input a byte at a time, so even large files hash quickly. The result is shown as an 8-digit hexadecimal value and as an unsigned 32-bit decimal number.
Text is hashed as UTF-8 bytes, so the checksum matches what other tools produce for the same content. CRC32 is a fast integrity check for detecting accidental corruption — it is not a cryptographic hash and should not be used for security. Files you pick are read locally in your browser and never uploaded.