Here is the text of the NIST sp800-63b Digital Identity Guidelines.
But it really doesn’t, unless you’re sending megabytes of text or something. Industry standard password algorithms run the hash a lot of times, and your entry will only impact the first iteration.
I usually set mine to 256 characters to prevent DOS attacks, and also so I don’t need to update it ever. Most of my passwords are actually around 20-30 characters in length (I pick a random length in the slider on my password manager), because I don’t want to be there all day if I ever need to manually enter it (looking at you stupid smart TV…).
unless you’re sending megabytes of text or something
That’s exactly what someone malicious would do though, either in a single password submission or DOS via the password maximum repeatedly. IMO there is no functional security difference between a 64 and a 256 character password, so the NIST 64 character max is reasonable.
