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Wanting to know if a password got pwned, so I head over to haveibeenpwned.com, there's a box there saying HEY CHAMP, TYPE IN YOUR PASSWORD TO SEE IF IT'S BEEN PWNED, I'm like haha no mate just gimme the list, it's all WHOA THERE BUDDY YOU NEED SPECIAL SOFTWARE TO DOWNLOAD PWNEDPASSWORDS.TXT, WE'VE MADE A PROGRAM TO DOWNLOAD THIS TEXT FILE, I'm like what, why can't I just, like, use this web browser that I'm using right now, or hell if you gimme a magnet link I can head upstairs and fire up bittorrent if it's THAT big, what the hell

Folks who have done this, what on earth is going on here and why and how do I check for a pwned password without... all that?