Compare files via CRC

Question

I have 2 zip files. Inside each zip file there are multiple text and binary files. However not all files are the same. Some files are different due to time stamp and other data, others are identical.

Can I use CRC to definitively prove that specific files are identical?

Example: I have file A,B,C in both archives. Can I use CRC to prove that A,B,C files is identical in both archives?

Thank you.

Answer 1

Definitively? No - CRC collisions are perfectly possible, just very improbable.

If you need absolute proof then you're going to need to compare the files byte-for-byte. If you just mean within the expectations of everyday use, sure. If the filesize is the same and the CRC is the same then it's very very likely the files are the same.

Answer 2

Definitively? No - CRC collisions are perfectly possible, just very improbable.

If you need absolute proof then you're going to need to compare the files byte-for-byte. If you just mean within the expectations of everyday use, sure. If the filesize is the same and the CRC is the same then it's very very likely the files are the same.