Comment by belval

2 years ago

95% means that on average only 1 in 20 keystroke will be wrong. Even if your password is very long (40-60) that means only 2-3 errors. Since more people are not machines their long password will be a combination of words like the famous "horsestaplebatterycorrect" example from xkcd.

Even if you flip a few letters from something like the above a human attacker will easily be able to fix it manually.

"horswstaplevatterucorrect" for example is still intelligible.

On average 2-3 errors. However the real thing we want to look at is what is my chance of guessing right across ALL characters. For 1 it's 95%, for 2 it's 90.2%, and it gets worse from there. The formula for accuracy would be .95^c where c is the number of characters in the password. So the chance of getting EVERY key correct in a 40 character password is < 13% and < 5% for 60 characters.

  • Right. The comment above is saying even if you are incorrect in 2-5 keystrokes it’s not hard to guess the correct keystrokes if you’re using a sentence style password.

    You don’t need to guess every character.