Don't!!!

CRC isn't a hashing algorithm. It's not designed for your purpose at all.

But let's assume it's somehow as good as MD5 (bit for bit) despite that, MD5's first 19 hex characters would be 18 trillion times better than CRC32.

                      Num of possible   Times better   Times better
                      hashes            than CRC32     md5_hex
===================   ===============   ============   ============
CRC32                          4.3E09
MD5 (19 of base 16)            7.6E22         1.8E13
MD5 (19 of base 62)            1.1E34         6.5E20         1.5E11
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