Cyclic Redundancy Check 32-bit (CRC32)

CRC32 stands for Cyclic Redundancy Check 32-bit. It is a hash function that produces a 32-bit, or 8-character hexadecimal, checksum or hash value from a given input, typically a sequence of bytes or a string. The primary purpose of CRC32 is error-checking and data integrity verification.

PHP calculates CRC32 values with the native crc32() function, and the hash() function, although with slight differences.

<?php

    $checksum = crc32("The quick brown fox jumped over the lazy dog.");
    printf("%u\n", $checksum);

    hash('crc32b', $str) === str_pad(dechex(crc32($str)), 8, '0', STR_PAD_LEFT);

?>

Documentation

See also php hash(‘crc32’) and crc32() return different value.

Related : To Crypt, Hash, Checksum