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by runnerup 1587 days ago
To me it seems like the password is 14 bytes, because they're 14 characters (112 bits). How do you get 90 bits?

It also uses 96 possible characters for each digit. Just storing the 96^14 different passwords without even adding their corresponding SHA hashes would require 5646 yottabytes. Which is more than 4 orders of magnitude larger than all the world's digital storage capacity combined together.

1 comments

As you say, each of the characters is not a full 8 bits (namely a character out of an alphabet of 256), but chosen from a smaller alphabet of 96 characters, and log(96)/log(2) = log_2(96) ≈ 6.58, so 6.58 * 14 = 92 bits. Then I deducted a bit or two ad-hoc for the way they're drawn, with letters overrepresented. This could be computed more precisely. But it's not more than 93 bits, and not less than 83 bits, I'd say.
Thank you so, so much for explaining this.