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I often (almost always) see that the password i choose in a service is limited (to 16, 30, whatever characters).
Are there any reasons for such a limit, provided that it is stored correctly? In such a case its hash will have a fixed length independently of its size.
I can imagine that there could be a limit on the size of the transaction in order not to impact the server (a 12 GB password could hang it, hit some limits etc.). An undisclosed limit of, say, 10000 characters could make sense in that case but I fail to understand the rationale for a 8/16/30/50/etc. characters limit.