What is the probability of guessing (matching) a Guid?

Question

Just curious but what is the probability of matching a Guid?

Say a Guid from SQL server: 5AC7E650-CFC3-4534-803C-E7E5BBE29B3D

is it a factorial?: (36*32)! =

Answer 1

Depends on the type of GUID generation algorithm. Current algorithms use 124 random bits so the probability is 1 in 2^124.

With older algorithms (that use time and MAC address) the probability is much higher.