Create your own MD5 collisions

Question

I\'m doing a presentation on MD5 collisions and I\'d like to give people any idea how likely a collision is.

It would be good to have two blocks of text which hash t

Answer 1

If you're talking about how likely a straightforward collision is - one where there is no deliberate attempt to cause one - then you're going to be disappointed: You'd need to generate on average 2^64 plaintexts before you can expect to see a collision, and that's substantially more than you're going to be able to do in a reasonable (or really, even an _un_reasonable) time.

If you're looking to demonstrate the difficulty of deliberately crafting a collision, other answers have already demonstrated that. The extra constraint of requiring the strings to be entirely textual makes even those approaches largely impractical, though.