The application has nothing to do with either cryptography or security. Essentially I want a hashing function with (far) less risk/frequency of collisions than a 32-bit hashing function, and far less space utilisation that a 128-bit digest.

Assuming linear distribution (and unlimited space), a 64-bit hash has only a 0.000000023% chance of collisions relative to a 32-bit hash. but uses half as much space as MD5.

I also considered 48-bit, but they're harder to calculate; and 53-bit (because of the possibility of using doubles for the calculations), but most hashing algorithm using shifting and that doesn't work with FP. And both are as rare as rocking horse doo-doo.

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In reply to Re^2: 64-bit digest algorithms by BrowserUk
in thread 64-bit digest algorithms by BrowserUk

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