Cyclic Redundancy Check 64 bit (CRC-64) Hash Checksum Generator
Cyclic Redundancy Check (CRC) is an error detection code used to detect changes and verify the data, usually on data transmission.
In the real world, usually CRC used when sending data. Lets say we want to send our message to someone else, to make sure the data didn't go through unintended changes (small changes, maybe because it goes through unreliable connection/wire), we can put CRC hash in the message. Upon receiving the message, the recipient try to calculate the CRC of the message and compare it to the CRC sent which included on the message. If the CRC hash is different, then there's a possibility of data change on the message. Though, this way not hacker-proof since, the hacker (or man in the middle) can also change the CRC hash to be the same as the CRC of message modified.
CRC often called a checksum, but it is not a sum, because it is represented as long binary number instead of the sum. It also involving polynomial expression.
Checking can be used for some applications such as data transmission
Let's say we have this data (represented in binary) :
1111 0000 1111 1111
And then we send the data over the network, after that the recipient receive:
1111 0001 1111 1111
Notice that one bit is changed, if we use checksum, we can detect this sort of thing.
This tool support ISO and ECMA table.
This tool support 64 / 65 bit only, if you want 32 / 33 bit, you can go to Cyclic Redundancy Check 32 bit (CRC-32)